January SARs -- Converted by SEC Publisher, created by BCL Technologies Inc., for SEC Filing

UNITED STATES
SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549

FORM N-CSRS

CERTIFIED SHAREHOLDER REPORT OF REGISTERED MANAGEMENT
INVESTMENT COMPANIES

Investment Company Act file number 811-07156

Name of Fund: BlackRock MuniYield Insured Investment Fund (MFT)

Fund Address: 100 Bellevue Parkway, Wilmington, DE 19809

Name and address of agent for service: Donald C. Burke, Chief Executive Officer, BlackRock
MuniYield Insured Investment Fund, 800 Scudders Mill Road, Plainsboro, NJ, 08536.
Mailing address: P.O. Box 9011, Princeton, NJ, 08543-9011

Registrant’s telephone number, including area code: (800) 882-0052, Option 4

Date of fiscal year end: 07/31/2009

Date of reporting period: 08/01/2008 – 01/31/2009

Item 1 – Report to Stockholders


EQUITIES FIXED INCOME REAL ESTATE LIQUIDITY ALTERNATIVES BLACKROCK SOLUTIONS

Semi-Annual Report

JANUARY 31, 2009 | (UNAUDITED)

BlackRock MuniHoldings New Jersey Insured Fund, Inc. (MUJ)

BlackRock MuniYield Insured Investment Fund (MFT)

BlackRock MuniYield Michigan Insured Fund, Inc. (MIY)

BlackRock MuniYield New Jersey Insured Fund, Inc. (MJI)

BlackRock MuniYield Pennsylvania Insured Fund (MPA)


NOT FDIC INSURED

MAY LOSE VALUE

NO BANK GUARANTEE


Table of Contents     
 
    Page 
A Letter to Shareholders    3 
Semi-Annual Report:     
Fund Summaries    4 
The Benefits and Risks of Leveraging    9 
Derivative Instruments    9 
Financial Statements:     
       Schedules of Investments    10 
       Statements of Assets and Liabilities    29 
       Statements of Operations    30 
       Statements of Changes in Net Assets    32 
Financial Highlights    35 
Notes to Financial Statements    40 
Officers and Directors/Trustees    47 
Additional Information    48 

2 SEMI-ANNUAL REPORT

JANUARY 31, 2009


A Letter to Shareholders

Dear Shareholder

The present time may well be remembered as one of the most tumultuous periods in financial market history. Over the past year, the bursting of the

housing bubble and the resultant credit crisis swelled into an all-out global financial market meltdown that featured the collapse of storied financial

firms, volatile swings in the world’s financial markets and monumental government responses, including the nearly $800 billion economic stimulus

plan signed into law just after period end.

The US economy appeared relatively resilient through the first few months of 2008, when rising food and energy prices fueled inflation fears. Mid-

summer ushered in dramatic changes — inflationary pressure subsided amid a plunge in commodity prices, while economic pressures intensified in

the midst of a rapid deterioration in consumer spending, employment and other key indicators. By year’s end, the National Bureau of Economic

Research affirmed that the United States was in a recession, which officially began in December 2007. The Federal Reserve Board (the “Fed”), after

slashing interest rates aggressively early in the period, resumed that rate-cutting campaign in the fall, with the final reduction in December 2008 bring-

ing the target federal funds rate to a record low range of between zero and 0.25% . Importantly, the central bank pledged that future policy moves to

revive the global economy and financial markets would comprise primarily nontraditional and quantitative easing measures, such as capital injections,

lending programs and government guarantees.

Against this backdrop, US equity markets experienced intense volatility, with the sentiment turning decisively negative toward period end. Declines were

significant and broad-based, with little divergence among large- and small-cap stocks. Non-US stocks posted stronger results early on, but quickly lost

ground as the credit crisis revealed itself to be global in scope and as the worldwide economic slowdown gathered pace. Overall, aggressive monetary

and fiscal policy, combined with the defensiveness of the US, helped domestic equities notch better performance than their non-US counterparts.

In fixed income markets, risk aversion remained the popular theme, leading the Treasury sector to top all other asset classes. The high yield market

was particularly hard hit in this environment, as economic turmoil, combined with frozen credit markets and substantial technical pressures, took a

heavy toll. Meanwhile, the municipal bond market was challenged by a dearth of market participants, lack of liquidity, difficult funding environment and

backlog of new-issue supply, which sent prices lower and yields well above Treasuries. By period end, however, some positive momentum had returned

to the municipal space.

In all, an investor flight to safety prevailed, as evidenced in the six- and 12-month returns of the major benchmark indexes:     
Total Returns as of January 31, 2009    6-month    12-month 
US equities (S&P 500 Index)    (33.95)%    (38.63)% 
Small cap US equities (Russell 2000 Index)    (37.38)    (36.84) 
International equities (MSCI Europe, Australasia, Far East Index)    (40.75)    (43.74) 
US Treasury securities (Merrill Lynch 10-Year US Treasury Index)    11.96    10.64 
Taxable fixed income (Barclays Capital US Aggregate Bond Index*)    3.23    2.59 
Tax-exempt fixed income (Barclays Capital Municipal Bond Index*)    0.70    (0.16) 
High yield bonds (Barclays Capital US Corporate High Yield 2% Issuer Capped Index*)    (19.07)    (19.72) 

* Formerly a Lehman Brothers index.
Past performance is no guarantee of future results. Index performance shown for illustrative purposes only. You cannot invest directly in an index.

Through periods of market turbulence, as ever, BlackRock’s full resources are dedicated to the management of our clients’ assets. For our most

current views on the economy and financial markets, we invite you to visit www.blackrock.com/funds. We thank you for entrusting BlackRock with

your investments, and we look forward to continuing to serve you in the months and years ahead.


THIS PAGE NOT PART OF YOUR FUND REPORT

3


Fund Summary as of January 31, 2009               BlackRock MuniHoldings New Jersey Insured Fund, Inc.

Investment Objective

BlackRock MuniHoldings New Jersey Insured Fund, Inc. (MUJ) (the “Fund”) seeks to provide shareholders with current income exempt from federal
income tax and New Jersey personal income taxes by investing in a portfolio of long-term, investment grade municipal obligations the interest on
which, in the opinion of bond counsel to the issuer, is exempt from federal income tax and New Jersey personal income taxes.

Performance

For the six months ended January 31, 2009, the Fund returned (7.46)% based on market price and (0.56)% based on net asset value (“NAV”). For
the same period, the closed-end Lipper Single-State Insured Municipal Debt Funds category posted an average return of (10.16)% on a market price
basis and (6.34)% on a NAV basis. All returns reflect reinvestment of dividends. The performance of the Lipper category does not necessarily correlate
to that of the Fund, as the Lipper group comprises funds representing various states and not New Jersey alone. The Fund’s discount to NAV, which
widened during the period, accounts for the difference between performance based on price and performance based on NAV. Fund performance was
driven primarily by a rising yield (and correspondingly falling price) environment for intermediate and long-term municipals during the second half of
2008. Pre-refunded and escrowed issues were the best-performing municipal sectors for the period, and the Fund’s high allocation to these areas
had a positive influence on results.

The views expressed reflect the opinions of BlackRock as of the date of this report and are subject to change based on changes in market, economic or other conditions.
These views are not intended to be a forecast of future events and are no guarantee of future results.

Fund Information                         
 
    Symbol on New York Stock Exchange                    MUJ 
    Initial Offering Date                March 11, 1998 
    Yield on Closing Market Price as of January 31, 2009 ($11.63)1                5.47% 
    Tax Equivalent Yield2                    8.42% 
    Current Monthly Distribution per Common Share3                    $0.053 
    Current Annualized Distribution per Common Share3                    $0.636 
    Leverage as of January 31, 20094                    39% 
   
 
 
 
 
 
       1 Yield on closing market price is calculated by dividing the current annualized distribution per share by the closing market price. 
           Past performance does not guarantee future results.                     
       2 Tax equivalent yield assumes the maximum federal tax rate of 35%.                 
       3 The distribution is not constant and is subject to change.                     
       4 Represents Auction Market Preferred Shares (“Preferred Shares”) and tender option bond trusts (“TOBs”) as a percentage of total managed 
           assets, which is the total assets of the Fund, including any assets attributable to Preferred Shares and TOBs, minus the sum of accrued liabilities. 
           For a discussion of leveraging techniques utilized by the Fund, please see The Benefits and Risks of Leveraging on page 9.     
    The table below summarizes the changes in the Fund’s market price and NAV per share:         
   
 
 
        1/31/09    7/31/08    Change    High    Low 
    Market Price    $11.63    $12.93    (10.05)%    $13.20    $ 8.38 
    Net Asset Value    $13.87    $14.35    (3.34)%    $14.69    $11.95 

The following charts show the sector and credit quality allocations of the Fund’s long-term investments:

Sector Allocations         
 
    1/31/09    7/31/08 
Transportation    27%    27% 
Education    17    18 
State    11    10 
IDA/PCR/Resource Recovery    10    10 
County/City/Special District/         
  School District    8    8 
Hospitals/Healthcare    7    8 
Housing    7    5 
Lease Obligations    6    7 
Special Tax    2    1 
Utilities — Water & Sewer    4    4 
Utilities — Electric & Gas    1    2 

     Credit Quality Allocations5         
 
    1/31/09    7/31/08 
AAA/Aaa    37%    43% 
AA/Aa    36    36 
A/A    19    14 
BBB/Baa    8    6 
Not Rated        16 

5 Using the higher of Standard & Poor’s (“S&P’s”) and Moody’s
Investors Service (“Moody’s”) ratings.
6 The investment advisor has deemed certain of these non-rated
securities to be of investment grade quality. As of July 31, 2008
the market value of these securities was $1,972,106, represent-
ing 1% of the Fund’s long-term investments.

4 SEMI-ANNUAL REPORT

JANUARY 31, 2009


Fund Summary as of January 31, 2009 BlackRock MuniYield Insured Investment Fund

Investment Objective

BlackRock MuniYield Insured Investment Fund (MFT) (the “Fund”) seeks to provide shareholders with as high a level of current income exempt from
federal income taxes as is consistent with its investment policies and prudent investment management by investing primarily in a portfolio of long-
term, investment grade municipal obligations the interest on which, in the opinion of bond counsel to the issuers, is exempt from federal income taxes
and which enables shares of the Fund to be exempt from Florida intangible personal property taxes.

Effective September 16, 2008, BlackRock MuniYield Florida Insured Fund was renamed BlackRock MuniYield Insured Investment Fund.

Performance

For the six months ended January 31, 2009, the Fund returned (7.54)% based on market price and (6.49)% based on NAV. For the same period, the
closed-end Lipper Insured Municipal Debt Funds (Leveraged) category posted an average return of (4.58)% on a market price basis and (6.20)% on
a NAV basis. All returns reflect reinvestment of dividends. The Fund’s discount to NAV, which widened during the period, accounts for the difference
between performance based on price and performance based on NAV. Sector allocation played an important role in determining how the Fund per-
formed during the reporting period. A significant overweight in pre-refunded bonds in the one- to five-year maturity range benefited Fund performance,
as the yield curve steepened and these issues outperformed. Conversely, an overweight position in hospital bonds adversely affected results, as spread
products underperformed as the economic downturn continued to add more stress on the fundamental credit quality of the sector.

The views expressed reflect the opinions of BlackRock as of the date of this report and are subject to change based on changes in market, economic or other conditions.
These views are not intended to be a forecast of future events and are no guarantee of future results.

Fund Information         
 
    Symbol on New York Stock Exchange    MFT 
    Initial Offering Date    October 30, 1992 
    Yield on Closing Market Price as of January 31, 2009 ($10.51)1               6.11% 
    Tax Equivalent Yield2               9.40% 
    Current Monthly Distribution per Common Share3    $0.0535 
    Current Annualized Distribution per Common Share3    $0.6420 
    Leverage as of January 31, 20094    41% 

1 Yield on closing market price is calculated by dividing the current annualized distribution per share by the closing market price.
Past performance does not guarantee future results.
2 Tax equivalent yield assumes the maximum federal tax rate of 35%.
3 The distribution is not constant and is subject to change.
4 Represents Preferred Shares and TOBs as a percentage of total managed assets, which is the total assets of the Fund, including any assets
attributable to Preferred Shares and TOBs, minus the sum of accrued liabilities. For a discussion of leveraging techniques utilized by the Fund,
please see The Benefits and Risks of Leveraging on page 9.

The table below summarizes the changes in the Fund’s market price and NAV per share:

    1/31/09    7/31/08    Change    High    Low 
Market Price    $10.51    $11.75    (10.55)%    $11.97    $ 6.70 
Net Asset Value    $12.14    $13.42    (9.54)%    $13.68    $10.36 

The following charts show the sector and credit quality allocations of the Fund’s long-term investments:

     Sector Allocations         
    1/31/09    7/31/08 
Transportation    25%    23% 
Education    20    19 
Hospitals/Healthcare    16    15 
County/City/Special District/         
   School District    9    12 
IDA/PCR/Resource Recovery    9    8 
Utilities — Electric & Gas    6    5 
Utilities — Irrigation, Resource         
   Recovery, Solid Waste & Other    6    6 
Utilities — Water & Sewer    4    3 
Housing    3    5 
Special Tax    1    1 
Lease Obligations    1    2 
State        1 

     Credit Quality Allocations5         
    1/31/09    7/31/08 
AAA/Aaa    42%    41% 
AA/Aa    37    41 
A/A    16    12 
BBB/Baa    3    1 
Not Rated6    2    5 

5 Using the higher of S&P’s or Moody’s ratings.
6 The investment advisor has deemed certain of these non-rated
securities to be of investment grade quality. As of January 31,
2009 and July 31, 2008, the market value of these securities
was $2,431,430, representing 1% and $8,223,585, representing
4%, respectively, of the Fund’s long-term investments.

SEMI-ANNUAL REPORT JANUARY 31, 2009 5


Fund Summary as of January 31, 2009           BlackRock MuniYield Michigan Insured Fund, Inc.

Investment Objective

BlackRock MuniYield Michigan Insured Fund, Inc. (MIY) (the “Fund”) seeks to provide shareholders with as high a level of current income exempt from
federal income tax and Michigan income taxes as is consistent with its investment policies and prudent investment management by investing primarily
in a portfolio of long-term municipal obligations the interest on which, in the opinion of bond counsel to the issuers, is exempt from federal income tax
and Michigan income taxes.

Performance

For the six months ended January 31, 2009, the Fund returned (11.04)% based on market price and (1.89)% based on NAV. For the same period, the
closed-end Lipper Single-State Insured Municipal Debt Funds category posted an average return of (10.16)% on a market price basis and (6.34)% on a
NAV basis. All returns reflect reinvestment of dividends. The performance of the Lipper category does not necessarily correlate to that of the Fund, as the
Lipper group comprises funds representing various states and not Michigan alone. The Fund’s discount to NAV, which widened during the period, accounts
for the difference between performance based on price and performance based on NAV. Fund performance was driven primarily by a rising yield (and cor-
respondingly falling price) environment for intermediate and long-term municipals during the second half of 2008. Pre-refunded and escrowed issues were
the best-performing municipal sectors for the period, and the Fund’s high allocation to these areas had a positive influence on results.

The views expressed reflect the opinions of BlackRock as of the date of this report and are subject to change based on changes in market, economic or other conditions.
These views are not intended to be a forecast of future events and are no guarantee of future results.

Fund Information         
    Symbol on New York Stock Exchange    MIY 
    Initial Offering Date    October 30, 1992 
    Yield on Closing Market Price as of January 31, 2009 ($10.61)1               6.11% 
    Tax Equivalent Yield2               9.40% 
    Current Monthly Distribution per Common Share3    $0.054 
    Current Annualized Distribution per Common Share3    $0.648 
    Leverage as of January 31, 20094    40% 

1 Yield on closing market price is calculated by dividing the current annualized distribution per share by the closing market price.
Past performance does not guarantee future results.
2 Tax equivalent yield assumes the maximum federal tax rate of 35%.
3 The distribution is not constant and is subject to change.
4 Represents Preferred Shares and TOBs as a percentage of total managed assets, which is the total assets of the Fund, including any assets
attributable to Preferred Shares and TOBs, minus the sum of accrued liabilities. For a discussion of leveraging techniques utilized by the Fund,
please see The Benefits and Risks of Leveraging on page 9.


The table below summarizes the changes in the Fund’s market price and NAV per share:

    1/31/09    7/31/08    Change    High    Low 
Market Price    $10.61    $12.30    (13.74)%    $12.43    $ 7.00 
Net Asset Value    $13.47    $14.16    (4.87)%    $14.50    $11.89 

The following charts show the sector and credit quality allocations of the Fund’s long-term investments:

     Sector Allocations         
 
    1/31/09    7/31/08 
County/City/Special District/         
   School District    24%    27% 
Hospitals/Healthcare    14    13 
Utilities — Water & Sewer    14    12 
Transportation    12    12 
Lease Obligations    10    8 
IDA/PCR/Resource Recovery    8    7 
Education    8    7 
Utilities — Electric & Gas    6    6 
Housing    2    2 
State    1    2 
Special Tax    1    1 
Utilities — Irrigation, Resource         
   Recovery, Solid Waste & Other        3 

     Credit Quality Allocations5         
    1/31/09    7/31/08 
AAA/Aaa    31%    35% 
AA/Aa    42    47 
A/A    24    15 
BBB/Baa    2    3 
NR    1     
 5 Using the higher of S&P’s or Moody’s ratings.     

6 SEMI-ANNUAL REPORT

JANUARY 31, 2009


Fund Summary as of January 31, 2009      BlackRock MuniYield New Jersey Insured Fund, Inc.

Investment Objective

BlackRock MuniYield New Jersey Insured Fund, Inc. (MJI) (the “Fund”) seeks to provide shareholders with as high a level of current income exempt
from federal income tax and New Jersey personal income taxes as is consistent with its investment policies and prudent investment management by
investing primarily in a portfolio of long-term municipal obligations the interest on which, in the opinion of bond counsel to the issuers, is exempt from
federal income tax and New Jersey personal income taxes.

Performance

For the six months ended January 31, 2009, the Fund returned (9.48)% based on market price and (3.14)% based on NAV. For the same period,
the closed-end Lipper Single-State Insured Municipal Debt Funds category posted an average return of (10.16)% on a market price basis and
(6.34)% on a NAV basis. All returns reflect reinvestment of dividends. The performance of the Lipper category does not necessarily correlate to that
of the Fund, as the Lipper group comprises funds representing various states and not New Jersey alone. The Fund’s discount to NAV, which widened
during the period, accounts for the difference between performance based on price and performance based on NAV. Fund performance was driven
primarily by a rising yield (and correspondingly falling price) environment for intermediate and long-term municipals during the second half of 2008.
Pre-refunded and escrowed issues were the best-performing municipal sectors for the period, and the Fund’s allocation to these areas had a positive
influence on results.

The views expressed reflect the opinions of BlackRock as of the date of this report and are subject to change based on changes in market, economic or other conditions.
These views are not intended to be a forecast of future events and are no guarantee of future results.

Fund Information         
    Symbol on New York Stock Exchange    MJI 
    Initial Offering Date    October 30, 1992 
    Yield on Closing Market Price as of January 31, 2009 ($11.24)1               5.77% 
    Tax Equivalent Yield2               8.88% 
    Current Monthly Distribution per Common Share3    $0.054 
    Current Annualized Distribution per Common Share3    $0.648 
    Leverage as of January 31, 20094    38% 

1 Yield on closing market price is calculated by dividing the current annualized distribution per share by the closing market price.
Past performance does not guarantee future results.
2 Tax equivalent yield assumes the maximum federal tax rate of 35%.
3 The distribution is not constant and is subject to change.
4 Represents Preferred Shares and TOBs as a percentage of total managed assets, which is the total assets of the Fund, including any assets
attributable to Preferred Shares and TOBs, minus the sum of accrued liabilities. For a discussion of leveraging techniques utilized by the Fund,
please see The Benefits and Risks of Leveraging on page 9.


The table below summarizes the changes in the Fund’s market price and NAV per share:

    1/31/09    7/31/08    Change    High    Low 
Market Price    $11.24    $12.81    (12.26)%    $13.02    $ 7.19 
Net Asset Value    $13.36    $14.23    (6.11)%    $14.58    $11.39 

The following charts show the sector and credit quality allocations of the Fund’s long-term investments:

Sector Allocations         
 
    1/31/09    7/31/08 
Transportation    20%    18% 
Education    16    15 
IDA/PCR/Resource Recovery    14    14 
Utilities — Water & Sewer    9    10 
State    9    8 
Housing    8    9 
County/City/Special District/         
   School District    8    8 
Hospitals/Healthcare    8    10 
Lease Obligations    6    5 
Utilities — Electric & Gas    2    3 

     Credit Quality Allocations5         
    1/31/09    7/31/08 
AAA/Aaa    31%    33% 
AA/Aa    37    46 
A/A    26    11 
BBB/Baa    4    4 
Not Rated6    2    6 

5 Using the higher of S&P’s or Moody’s ratings.
6 The investment advisor has deemed certain of these non-rated
securities to be of investment grade quality. As of January 31,
2009 and July 31, 2008, the market value of these securities
was $4,305,850, representing 2% and $12,649,795, represent-
ing 6%, respectively, of the Fund’s long-term investments.

SEMI-ANNUAL REPORT

JANUARY 31, 2009

7


Fund Summary as of January 31, 2009 BlackRock MuniYield Pennsylvania Insured Fund

Investment Objective

BlackRock MuniYield Pennsylvania Insured Fund (MPA) (the “Fund”) seeks to provide shareholders with as high a level of current income exempt from fed-
eral and Pennsylvania income taxes as is consistent with its investment policies and prudent investment management by investing primarily in a portfolio of
long-term municipal obligations the interest on which, in the opinion of bond counsel to the issuers, is exempt from federal and Pennsylvania income taxes.

Performance

For the six months ended January 31, 2009, the Fund returned (7.30)% based on market price and (2.63)% based on NAV. For the same period, the
closed-end Lipper Single-State Insured Municipal Debt Funds category posted an average return of (10.16)% on a market price basis and (6.34)%
on a NAV basis. All returns reflect reinvestment of dividends. The Fund’s discount to NAV, which widened during the period, accounts for the difference
between performance based on price and performance based on NAV. Recent Fund performance, based on net expenses, has been positively affected
by its defensive posture during the period. Exposure to the intermediate portion of the municipal yield curve benefited performance as the curve steep-
ened to wider ranges. An emphasis on higher credit quality bonds also aided results as credit spread widening peaked during the period. All hedges were
eliminated during the period as correlation to the municipal cash market broke down. Positions in lower-rated issues and issues subject to the alternative
minimum tax hindered performance. The Fund maintained a mean distribution rate and was underweight duration relative to its Lipper peers.

The views expressed reflect the opinions of BlackRock as of the date of this report and are subject to change based on changes in market, economic or other conditions.
These views are not intended to be a forecast of future events and are no guarantee of future results.

Fund Information         
    Symbol on New York Stock Exchange    MPA 
    Initial Offering Date    October 30, 1992 
    Yield on Closing Market Price as of January 31, 2009 ($11.18)1               5.69% 
    Tax Equivalent Yield2               8.75% 
    Current Monthly Distribution per Common Share3    $0.053 
    Current Annualized Distribution per Common Share3    $0.636 
    Leverage as of January 31, 20094    36% 

1 Yield on closing market price is calculated by dividing the current annualized distribution per share by the closing market price.
Past performance does not guarantee future results.
2 Tax equivalent yield assumes the maximum federal tax rate of 35%.
3 The distribution is not constant and is subject to change.
4 Represents Preferred Shares and TOBs as a percentage of total managed assets, which is the total assets of the Fund, including any assets
attributable to Preferred Shares and TOBs, minus the sum of accrued liabilities. For a discussion of leveraging techniques utilized by the Fund,
please see The Benefits and Risks of Leveraging on page 9.

The table below summarizes the changes in the Fund’s market price and NAV per share:

    1/31/09    7/31/08    Change    High    Low 
Market Price    $11.18    $12.43    (10.06)%    $12.61    $ 7.09 
Net Asset Value    $13.51    $14.30    (5.52)%    $14.66    $11.00 

The following charts show the sector and credit quality allocations of the Fund’s long-term investments:

Sector Allocations         
    1/31/09    7/31/08 
County/City/Special District/         
   School District    32%    33% 
Education    24    22 
Transportation    14    12 
IDA/PCR/Resource Recovery    14    15 
Hospitals/Healthcare    6    7 
Housing    4    3 
Utilities — Water & Sewer    3    4 
Utilities — Electric & Gas    3    4 

     Credit Quality Allocations5         
    1/31/09    7/31/08 
AAA/Aaa    42%     48% 
AA/Aa    50    35 
A/A    8    14 
BBB/Baa        3 

 
 
 5 Using the higher of S&P’s or Moody’s ratings.     

8 SEMI-ANNUAL REPORT

JANUARY 31, 2009


The Benefits and Risks of Leveraging

The Funds may utilize leverage to seek to enhance the yield and NAV of
its Common Shares. However, these objectives cannot be achieved in all
interest rate environments.

To leverage, certain Funds issue Preferred Shares, which pay dividends at
prevailing short-term interest rates, and invests the proceeds in long-term
municipal bonds. In general, the concept of leveraging is based on the
premise that the cost of assets to be obtained from leverage will be based
on short-term interest rates, which normally will be lower than the income
earned by each Fund on its longer-term portfolio investments. To the
extent that the total assets of the Fund (including the assets obtained
from leverage) are invested in higher-yielding portfolio investments, the
Fund’s Common Shareholders will benefit from the incremental yield.

To illustrate these concepts, assume a Fund’s Common Shares capitaliza-
tion is $100 million and it issues Preferred Shares for an additional
$50 million, creating a total value of $150 million available for investment
in long-term municipal bonds. If prevailing short-term interest rates are
3% and long-term interest rates are 6%, the yield curve has a strongly
positive slope. In this case, the Fund pays dividends on the $50 million of
Preferred Shares based on the lower short-term interest rates. At the same
time, the Fund’s total portfolio of $150 million earns the income based
on long-term interest rates. In this case, the dividends paid to Preferred
Shareholders are significantly lower than the income earned on the Fund’s
long-term investments, and therefore the Common Shareholders are the
beneficiaries of the incremental yield.

Conversely, if prevailing short-term interest rates rise above long-term
interest rates of 6%, the yield curve has a negative slope. In this case,
the Fund pays dividends on the higher short-term interest rates whereas
the Fund’s total portfolio earns income based on lower long-term interest
rates. If short-term interest rates rise, narrowing the differential between
short-term and long-term interest rates, the incremental yield pickup on
the Common Shares will be reduced or eliminated completely.

Furthermore, the value of the Fund’s portfolio investments generally varies
inversely with the direction of long-term interest rates, although other
factors can influence the value of portfolio investments. In contrast, the
redemption value of the Fund’s Preferred Shares does not fluctuate in rela-
tion to interest rates. As a result, changes in interest rates can influence
the Fund’s NAV positively or negatively in addition to the impact on Fund
performance from leverage from Preferred Shares discussed above.

Certain Funds may also, from time to time, leverage its assets through the
use of tender option bond (“TOB”) programs, as described in Note 1 of the
Notes to Financial Statements. TOB investments generally will provide the

Funds with economic benefits in periods of declining short-term interest
rates, but expose the Funds to risks during periods of rising short-term
interest rates similar to those associated with Preferred Shares issued by
the Funds, as described above. Additionally, fluctuations in the market
value of municipal bonds deposited into the TOB trust may adversely
affect the Funds’ NAV per share.

The use of leverage may enhance opportunities for increased returns to the
Funds and Common Shareholders, but as described above, it also creates
risks as short- or long-term interest rates fluctuate. Leverage also will gen-
erally cause greater changes in a Funds’ NAV, market price and dividend
rate than a comparable portfolio without leverage. If the income derived
from securities purchased with assets received from leverage exceeds the
cost of leverage, the Funds’ net income will be greater than if leverage had
not been used. Conversely, if the income from the securities purchased is
not sufficient to cover the cost of leverage, the Funds’ net income will be
less than if leverage had not been used, and therefore the amount avail-
able for distribution to shareholders will be reduced. The Funds may be
required to sell portfolio securities at inopportune times or below fair mar-
ket values in order to comply with regulatory requirements applicable to
the use of leverage or as required by the terms of leverage instruments,
which may cause the Funds to incur losses. The use of leverage may limit
the Funds’ ability to invest in certain types of securities or use certain
types of hedging strategies, such as in the case of certain restrictions
imposed by ratings agencies that rate preferred shares issued by a Fund.
The Funds will incur expenses in connection with the use of leverage, all of
which are borne by the holders of the Common Shares and may reduce
returns on the Common Shares.

Under the Investment Company Act of 1940, the Funds are permitted to
issue Preferred Shares in an amount of up to 50% of its total managed
assets at the time of issuance. Under normal circumstances, each Fund
anticipates that the total economic leverage from Preferred Shares and
TOBs will not exceed 50% of its total managed assets at the time such
leverage is incurred. As of January 31, 2009, the Funds had economic
leverage from Preferred Shares and TOBs as a percentage of their total
managed assets as follows:

    Percent of 
    Leverage 
BlackRock MuniHoldings New Jersey Insured Fund, Inc    39% 
BlackRock MuniYield Insured Investment Fund    41% 
BlackRock MuniYield Michigan Insured Fund, Inc    40% 
BlackRock MuniYield New Jersey Insured Fund, Inc    38% 
BlackRock MuniYield Pennsylvania Insured Fund    36% 

Derivative Instruments

The Funds may invest in various derivative instruments, including swaps
and other instruments specified in the Notes to Financial Statements,
which constitute forms of economic leverage. Such instruments are used
to obtain exposure to a market without owning or taking physical custody
of securities or to hedge market and/or interest rate risks. Such derivative
instruments involve risks, including the imperfect correlation between
the value of a derivative instrument and the underlying asset, possible
default of the other party to the transaction and illiquidity of the deriva-
tive instrument. The Funds’ ability to successfully use a derivative instru-

ment depends on the Advisor’s ability to accurately predict pertinent
market movements, which cannot be assured. The use of derivative instru-
ments may result in losses greater than if they had not been used, may
require the Funds to sell or purchase portfolio securities at inopportune
times or for prices other than current market values, may limit the amount
of appreciation the Funds can realize on an investment or may cause
the Funds to hold a security that they might otherwise sell. The Funds’
investments in these instruments are discussed in detail in the Notes
to Financial Statements.

SEMI-ANNUAL REPORT

JANUARY 31, 2009

9


Schedule of Investments January 31, 2009 (Unaudited)    BlackRock MuniHoldings New Jersey Insured Fund, Inc. (MUJ) 
                    (Percentages shown are based on Net Assets) 
        Par                    Par     
Municipal Bonds        (000)    Value    Municipal Bonds        (000)    Value 
     New Jersey — 145.1%                    New Jersey (continued)             
County/City/Special District/School District — 12.9%            Education (concluded)             
Essex County, New Jersey, Improvement Authority                New Jersey State Educational Facilities Authority,             
 Revenue Bonds, Series A, 5%, 10/01/13 (b)(e)    $ 4,400    $ 5,091,900     Revenue Refunding Bonds:             
Hopatcong, New Jersey, GO, Sewer Refunding Bonds,                (College of New Jersey), Series D,             
 4.50%, 8/01/33 (a)        2,690    2,439,104        5%, 7/01/35 (c)    $ 9,540    $ 9,347,769 
Jersey City, New Jersey, GO, Series B,                    (Montclair State University), Series J,             
 5.25%, 9/01/11 (b)(c)        1,000    1,125,780        4.25%, 7/01/30 (d)        3,775    3,118,943 
Lafayette Yard, New Jersey, Community Development                    (Montclair State University), Series L,             
 Revenue Bonds (Hotel/Conference Center Project-                5%, 7/01/14 (b)(d)        7,510    8,770,854 
 Trenton), 6%, 4/01/10 (b)(d)        5,250    5,610,727        (Ramapo College), Series I, 4.25%, 7/01/31 (a)    1,250    1,032,213 
Middlesex County, New Jersey, Improvement Authority                (Ramapo College), Series I, 4.25%, 7/01/36 (a)    900    716,256 
 Revenue Bonds (Senior Citizens Housing Project),                    (Rowan University), Series C,             
 AMT, 5.50%, 9/01/30 (a)        500    435,080        5.25%, 7/01/11 (b)(e)        790    876,354 
Monmouth County, New Jersey, Improvement Authority,                (Rowan University), Series C, 5.25%, 7/01/17 (e)    2,135    2,277,234 
 Governmental Loan Revenue Refunding Bonds (a):                (Rowan University), Series C, 5.25%, 7/01/18 (e)    2,535    2,697,113 
     5.35%, 12/01/10 (b)        695    752,421        (Rowan University), Series C, 5.25%, 7/01/19 (e)    2,370    2,499,592 
     5.375%, 12/01/10 (b)        535    579,448    New Jersey State Educational Facilities Authority,             
     5.35%, 12/01/17        845    885,408     (Stevens Institute of Technology), Series A:             
     5.375%, 12/01/18        935    980,226        5%, 7/01/27        2,800    2,141,468 
Perth Amboy, New Jersey, GO (Convertible CABS),                    5%, 7/01/34        900    635,958 
 Refunding, 5.711%, 7/01/37 (c)(f)        1,470    1,098,707    North Bergen Township, New Jersey, Board of Education,         
Salem County, New Jersey, Improvement Authority                 COP (b)(c):             
 Revenue Bonds (Finlaw State Office Building Project),                6%, 12/15/10        1,000    1,106,060 
 5.375%, 8/15/28 (c)        500    516,050        6.25%, 12/15/10        1,580    1,754,906 
Trenton, New Jersey, Parking Authority, Parking Revenue            Paterson, New Jersey, Public School District, COP (b)(d):         
 Bonds, 6.10%, 4/01/10 (b)(e)        8,650    9,209,828        6.125%, 11/01/09        1,980    2,083,693 
West Deptford Township, New Jersey, GO,                    6.25%, 11/01/09        2,000    2,106,620 
 5.625%, 9/01/10 (b)(e)        8,580    9,242,290    University of Medicine and Dentistry of New Jersey, COP,         
            37,966,969     5%, 6/15/29 (d)        2,000    1,661,720 
                University of Medicine and Dentistry of New Jersey,             
Education — 27.9%                 Revenue Bonds, Series A, 5.50%, 12/01/27 (a)        4,740    4,310,177 
New Jersey EDA, Lease Revenue Bonds (University of                             
 Medicine and Dentistry-International Center for                                82,393,729 
 Public Health Project), 6%, 6/01/32 (a)        5,000    4,276,100    Hospitals/Healthcare — 10.6%             
New Jersey State Educational Facilities Authority, Higher            New Jersey Health Care Facilities Financing Authority,         
 Education, Capital Improvement Revenue Bonds,                 Department of Human Services Revenue Bonds             
 Series A, 5.125%, 9/01/12 (a)(b)        7,500    8,507,550     (Greystone Park Psychiatric Hospital Project),             
New Jersey State Educational Facilities Authority                 5%, 9/15/23 (a)        10,775    10,555,513 
 Revenue Bonds:                New Jersey Health Care Facilities Financing Authority         
     (Capital Improvement Fund), Series A,                 Revenue Bonds:             
     5.75%, 9/01/10 (b)(c)        9,420    10,165,687        (Society of the Valley Hospital),             
     (Montclair State University), Series A,                    5.375%, 7/01/25 (a)        2,820    2,362,201 
     5%, 7/01/21 (a)        1,200    1,262,964        (Somerset Medical Center), 5.50%, 7/01/33        2,135    1,076,744 
     (Montclair State University), Series A,                    (South Jersey Hospital System), 6%, 7/01/12 (b)    5,440    6,258,829 
     5%, 7/01/22 (a)        2,880    2,991,974                     
     (Rowan University), Series C, 5%, 7/01/14 (b)(d)    3,260    3,807,321                     
     (Rowan University), Series C,                                 
     5.125%, 7/01/14 (b)(d)        3,615    4,245,203                     

Portfolio Abbreviations                 
To simplify the listings of portfolio holdings in the    AMT    Alternative Minimum Tax (subject to)    HFA    Housing Finance Agency 
Schedules of Investments, the names and descriptions    CABS    Capital Appreciation Bonds    IDA    Industrial Development Authority 
of many of the securities have been abbreviated    COP    Certificates of Participation    IDR    Industrial Development Revenue Bonds 
according to the list on the right.    DRIVERS    Derivative Inverse Tax-Exempt Receipts    M/F    Multi-Family 
    EDA    Economic Development Authority    PCR    Pollution Control Revenue Bonds 
    EDR    Economic Development Revenue Bonds    S/F    Single Family 
    GO    General Obligation Bonds    VRDN    Variable Rate Demand Notes 
  HDA    Housing Development Authority         
  See Notes to Financial Statements.           
 

10 SEMI-ANNUAL REPORT

JANUARY 31, 2009


Schedule of Investments (continued)    BlackRock MuniHoldings New Jersey Insured Fund, Inc. (MUJ) 
                (Percentages shown are based on Net Assets) 
        Par                Par     
Municipal Bonds        (000)    Value    Municipal Bonds        (000)    Value 
     New Jersey (continued)                     New Jersey (continued)             
Hospitals/Healthcare (concluded)                Lease Obligations — 9.5%             
New Jersey Health Care Facilities Financing Authority,            Camden County, New Jersey, Improvement Authority,             
 Revenue Refunding Bonds:                 Lease Revenue Bonds, 5.50%, 9/01/10 (b)(c)    $ 1,540     $ 1,655,854 
     (AHS Hospital Corporation), Series A,                Carteret, New Jersey, Board of Education, COP,             
     6%, 7/01/13 (a)(h)    $ 4,000    $ 4,721,760     6%, 1/15/10 (b)(d)        430    456,871 
     (Atlantic City Medical Center), 5.75%, 7/01/12 (b)    1,525    1,724,424    East Orange, New Jersey, Board of Education, COP,             
     (Atlantic City Medical Center), 6.25%, 7/01/12 (b)    530    608,058     5.50%, 8/01/12 (c)        7,895    8,485,151 
     (Atlantic City Medical Center), 6.25%, 7/01/17    925    958,244    Essex County, New Jersey, Improvement Authority,             
     (Atlantic City Medical Center), 5.75%, 7/01/25    1,975    1,927,797     Lease Revenue Bonds (Correctional Facility Project),         
     (Meridian Health System Obligation Group),                 6%, 10/01/10 (b)(e)        4,000    4,339,320 
     5.375%, 7/01/24 (c)        1,000    978,430    Middlesex County, New Jersey, COP,             
            31,172,000     5.25%, 6/15/23 (d)        1,550    1,557,858 
                Middlesex County, New Jersey, COP, Refunding,             
Housing — 3.5%                             
                 5.50%, 8/01/16 (d)        1,375    1,481,109 
New Jersey State Housing and Mortgage Finance                             
                New Jersey EDA, State Lease Revenue Bonds (State             
 Agency, Home Buyer Revenue Bonds, AMT,                             
                 Office Buildings Projects) (a)(b):             
 Series U (d):                             
                     6%, 6/15/10        3,000    3,220,530 
     5.60%, 10/01/12        700    706,069                 
                     6.25%, 6/15/10        4,620    4,975,417 
     5.65%, 10/01/13        2,075    2,092,845                 
                North Bergen Township, New Jersey, Board of             
     5.75%, 4/01/18        2,325    2,338,299                 
     5.85%, 4/01/29        610    595,976     Education, COP, 6.25%, 12/15/10 (b)(c)        1,680    1,865,976 
New Jersey State Housing and Mortgage Finance                            28,038,086 
 Agency Revenue Bonds, DRIVERS, Series 2619,                Special Tax — 2.8%             
 6.904%, 11/01/13 (c)(i)        4    3,395    Garden State Preservation Trust of New Jersey, Open         
New Jersey State Housing and Mortgage Finance                 Space and Farmland Preservation, Revenue             
 Agency Revenue Bonds, Series AA, 6.50%, 10/01/38    3,370    3,555,148     Refunding Bonds, Series C, 5.25%, 11/01/20 (c)    5,000    5,889,750 
New Jersey State Housing and Mortgage Finance                New Jersey Sports and Exposition Authority, State             
 Agency, S/F Housing Revenue Refunding Bonds, AMT,             Contract Revenue Bonds, Series A, 6%, 3/01/13 (d)    2,400    2,511,432 
 Series T, 4.70%, 10/01/37        800    622,344                 
Newark, New Jersey, Housing Authority, Port Authority-                        8,401,182 
 Port Newark Marine Terminal, Additional Rent-Backed            State — 14.6%             
 Revenue Refunding Bonds (City of Newark                Garden State Preservation Trust of New Jersey, Capital         
 Redevelopment Projects), 4.375%, 1/01/37 (d)        620    488,424     Appreciation Revenue Bonds, Series B (c)(g):             
            10,402,500         5.114%, 11/01/23        9,000    4,447,800 
                     5.195%, 11/01/25        10,000    4,273,200 
IDA/PCR/Resource Recovery — 16.6%                Garden State Preservation Trust of New Jersey, Open         
New Jersey EDA, Cigarette Tax Revenue Bonds:                 Space and Farmland Preservation Revenue Bonds,         
     5.625%, 6/15/19        2,700    2,292,354     Series A (c):             
     5.75%, 6/15/29 (j)        2,000    1,488,380         5.80%, 11/01/21        1,960    2,229,598 
     5.50%, 6/15/31 (j)        585    415,467         5.80%, 11/01/23        2,730    3,025,195 
     5.75%, 6/15/34 (j)        1,180    849,942    Garden State Preservation Trust of New Jersey,             
New Jersey EDA, Motor Vehicle Surcharge Revenue                 Open Space and Farmland Preservation, Revenue             
 Bonds, Series A (d):                             
                 Refunding Bonds, Series C, 5.25%, 11/01/21 (c)    7,705    8,963,766 
     5.25%, 7/01/26        7,500    7,474,200                 
                New Jersey Sports and Exposition Authority, Luxury Tax         
     5.25%, 7/01/33        11,105    10,394,502                 
                 Revenue Refunding Bonds (Convention Center) (d):         
     5%, 7/01/34        2,000    1,795,860                 
                     5.50%, 3/01/21        5,890    6,416,978 
New Jersey EDA, School Facilities Construction                             
                     5.50%, 3/01/22        3,000    3,217,290 
 Revenue Bonds:                             
                Perth Amboy, New Jersey, GO (Convertible CABS),             
     Series L, 5%, 3/01/30 (c)        9,000    8,593,290                 
                 Refunding (c)(f):             
     Series O, 5.25%, 3/01/23        4,420    4,507,339                 
                     5.225%, 7/01/32        4,605    3,533,877 
     Series U, 5%, 9/01/37 (a)        2,500    2,209,650                 
     Series Z, 6%, 12/15/34 (k)        2,800    2,922,724         5.22%, 7/01/33        1,395    1,061,525 
New Jersey EDA, School Facilities Construction,                Tobacco Settlement Financing Corporation of             
 Revenue Refunding Bonds, Series N-1,                 New Jersey, Asset-Backed Revenue Bonds,             
 5.50%, 9/01/27 (d)(e)        1,000    1,009,240     7%, 6/01/13 (b)        4,755    5,792,874 
New Jersey EDA, Solid Waste Disposal Facilities                            42,962,103 
 Revenue Bonds (Waste Management Inc.), AMT,                             
 Series A, 5.30%, 6/01/15        2,500    2,168,925                 
New Jersey EDA, State Lease Revenue Bonds,                             
(Liberty State Park Project), Series C, 5%, 3/01/22 (c)    2,670    2,806,250                 
            48,928,123                 

  See Notes to Financial Statements.

SEMI-ANNUAL REPORT JANUARY 31, 2009 11


Schedule of Investments (continued)    BlackRock MuniHoldings New Jersey Insured Fund, Inc. (MUJ) 
                (Percentages shown are based on Net Assets) 
        Par                Par     
Municipal Bonds        (000)    Value    Municipal Bonds        (000)    Value 
 
     New Jersey (continued)                     New Jersey (concluded)             
Transportation — 42.9%                Utilities — Water & Sewer — 3.8%             
Delaware River Port Authority of Pennsylvania and                Atlantic Highlands, New Jersey, Highland Regional             
 New Jersey Revenue Bonds (c):                 Sewer Authority, Sewer Revenue Refunding Bonds,         
     5.50%, 1/01/12    $ 5,000    $ 5,148,350     5.50%, 1/01/20 (d)(e)    $ 1,875    $ 1,973,700 
     5.625%, 1/01/13        6,000    6,175,320    New Jersey EDA, Water Facilities Revenue Bonds             
     5.75%, 1/01/15        500    513,190     (New Jersey-American Water Company, Inc. Project),         
     6%, 1/01/18        4,865    4,972,614     AMT, Series A, 5.25%, 11/01/32 (a)        3,000    2,387,250 
     6%, 1/01/19        5,525    5,634,616    North Hudson Sewage Authority, New Jersey, Sewer             
Delaware River Port Authority of Pennsylvania and                 Revenue Refunding Bonds, 5.125%, 8/01/20 (d)    4,335    4,663,810 
 New Jersey Revenue Bonds (Port District Project),                Rahway Valley Sewerage Authority, New Jersey,             
 Series B, 5.625%, 1/01/26 (c)        2,425    2,405,285     Sewer Revenue Bonds, CABS, Series A,             
Hudson County, New Jersey, Improvement Authority,                 4.788%, 9/01/28 (d)(g)        6,600    2,081,310 
 Parking Revenue Bonds (Harrison Parking Facility                            11,106,070 
 Project), Series C, 5.375%, 1/01/44 (k)        3,600    3,571,200                 
Morristown, New Jersey, Parking Authority Revenue                Total Municipal Bonds in New Jersey — 145.1%            427,700,928 
 Bonds (d):                             
     5%, 8/01/30        1,830    1,792,229         Puerto Rico — 9.7%             
     5%, 8/01/33        3,000    2,905,290                 
New Jersey State Transit Corporation, COP                Hospitals/Healthcare — 1.2%             
 (Federal Transit Administration Grants), Series A,                Puerto Rico Industrial, Tourist, Educational, Medical and         
 6.125%, 9/15/09 (a)(b)        2,500    2,581,200     Environmental Control Facilities Revenue Bonds, Series A:         
New Jersey State Transportation Trust Fund Authority,                 (Hospital Auxilio Mutuo Obligation Group),             
 Transportation System Revenue Bonds:                     6.25%, 7/01/24 (d)        1,780    1,709,370 
     Series A, 6%, 6/15/10 (b)        7,500    8,051,325         (Hospital de la Concepcion),             
     Series A, 5.625%, 12/15/28 (k)        2,000    2,077,400         6.50%, 11/15/20        1,750    1,802,448 
     Series A, 5%, 12/15/32 (a)        1,425    1,330,836                3,511,818 
     Series C, 5.50%, 6/15/13        1,030    1,204,770                 
     Series C, 4.712%, 12/15/32 (c)(g)        4,050    991,035    Housing — 2.1%             
     Series C, 5.049%, 12/15/35 (a)(g)        1,400    237,706    Puerto Rico Housing Financing Authority, Capital             
     Series C, 5.049%, 12/15/36 (a)(g)        5,500    871,860     Funding Program, Subordinate Revenue Refunding         
     Series D, 5%, 6/15/19 (c)        7,800    8,402,940     Bonds, 5.125%, 12/01/27        6,285    6,169,167 
New Jersey State Transportation Trust Fund Authority,            Lease Obligations — 0.7%             
 Transportation System Revenue Refunding Bonds:                Puerto Rico Public Buildings Authority, Government             
     Series A, 5.25%, 12/15/20 (c)        10,750    12,233,608     Facilities Revenue Refunding Bonds, Series M-3,             
     Series B, 5.50%, 12/15/21 (d)        9,165    10,075,359     6%, 7/01/27 (d)(l)        2,125    2,003,025 
New Jersey State Turnpike Authority, Turnpike Revenue            Transportation — 1.7%             
 Bonds, Series B, 5.926%, 1/01/35 (a)(g)        7,615    4,978,535    Puerto Rico Commonwealth Highway and Transportation         
New Jersey State Turnpike Authority, Turnpike Revenue             Authority, Highway Revenue Refunding Bonds,             
 Refunding Bonds, Series C (d):                 Series CC, 5.50%, 7/01/31 (k)        5,000    5,044,800 
     6.50%, 1/01/16 (h)        4,610    5,473,272                 
     6.50%, 1/01/16        910    1,124,951    Utilities — Electric & Gas — 1.9%             
Port Authority of New York and New Jersey, Consolidated            Puerto Rico Electric Power Authority, Power             
 Revenue Refunding Bonds, AMT, 152nd Series:                 Revenue Bonds:             
     5.75%, 11/01/30        5,175    4,957,857         Series HH, 5.25%, 7/01/10 (b)(c)        2,000    2,149,880 
     5.25%, 11/01/35        6,000    5,224,440         Series RR, 5%, 7/01/28 (m)        4,100    3,352,611 
Port Authority of New York and New Jersey, Special                            5,502,491 
 Obligation Revenue Bonds (JFK International Air                Utilities — Water & Sewer — 2.1%             
 Terminal LLC), AMT, Series 6 (d):                Puerto Rico Commonwealth Aqueduct and Sewer             
     6.25%, 12/01/11        13,500    13,625,010     Authority, Senior Lien Revenue Bonds, Series A,             
     6.25%, 12/01/15        1,500    1,431,540     5.125%, 7/01/47 (k)        6,870    5,692,963 
     5.75%, 12/01/25        3,000    2,294,460    Puerto Rico Commonwealth Infrastructure Financing         
South Jersey Port Corporation of New Jersey, Revenue             Authority, Special Tax and Capital Appreciation             
 Refunding Bonds:                 Revenue Bonds, Series A, 4.353%, 7/01/37 (a)(g)    4,000    466,600 
     4.50%, 1/01/15        3,750    4,008,038                 
     4.50%, 1/01/16        1,920    2,035,930                6,159,563 
            126,330,166    Total Municipal Bonds in Puerto Rico — 9.7%            28,390,864 
                Total Municipal Bonds — 154.8%            456,091,792 

See Notes to Financial Statements.

12 SEMI-ANNUAL REPORT JANUARY 31, 2009


Schedule of Investments (concluded) BlackRock MuniHoldings New Jersey Insured Fund, Inc. (MUJ)
(Percentages shown are based on Net Assets)

Municipal Bonds Transferred to    Par     
Tender Option Bond Trusts (n)    (000)    Value 
 
New Jersey — 8.8%         
Housing — 5.3%         
New Jersey State Housing and Mortgage Finance         
 Agency, Capital Fund Program Revenue Bonds,         
 Series A (c):         
    4.70%, 11/01/25    $ 4,790     $ 4,850,641 
    5%, 5/01/27    11,225    10,762,879 
            15,613,520 
State — 3.5%         
Garden State Preservation Trust of New Jersey, Open         
 Space and Farmland Preservation Revenue Bonds,         
 Series A, 5.75%, 11/01/28 (c)    9,160    10,375,440 
Total Municipal Bonds Transferred to         
Tender Option Bond Trusts — 8.8%        25,988,960 
Total Long-Term Investments         
(Cost — $484,682,250) — 163.6%    482,080,752 
 
Short-Term Securities    Shares     
Money Market Funds — 0.1%         
CMA New Jersey Municipal Money Fund, 0.22% (o)(p)    310,880    310,880 
Total Short-Term Securities         
(Cost — $310,880) — 0.1%        310,880 
Total Investments (Cost — $484,993,130*) — 163.7%    482,391,632 
Other Assets Less Liabilities — 1.4%        3,974,508 
Liability for Trust Certificates, Including Interest         
   Expense and Fees Payable — (5.1)%        (14,928,615) 
Preferred Shares, at Redemption Value — (60.0)%    (176,716,565) 
Net Assets Applicable to Common Shares — 100.0%    $294,720,960 
 
   * The cost and unrealized appreciation (depreciation) of investments as of 
    January 31, 2009, as computed for federal income tax purposes, were 
    as follows:         
 
    Aggregate cost    $471,344,025 
    Gross unrealized appreciation    $ 18,254,480 
    Gross unrealized depreciation        (22,031,873) 
    Net unrealized depreciation    $ (3,777,393) 
 
(a)    AMBAC Insured.         
(b)    US government securities, held in escrow, are used to pay interest on this 
    security as well as to retire the bond in full at the date indicated, typically at 
    a premium to par.         
(c)    FSA Insured.         
(d)    MBIA Insured.         
(e)    FGIC Insured.         
(f)    Represents a step-up bond that pays an initial coupon rate for the first period 
    and then a higher coupon rate for the following periods. Rate shown reflects the 
    current yield as of report date.         
(g)    Represents a zero-coupon bond. Rate shown reflects the current yield as of 
    report date.         
(h)    Security is collateralized by Municipal or US Treasury Obligations.     

(i)    Variable rate security. Rate shown is as of report date.     
(j)    Radian Insured.         
(k)    Assured Guaranty Insured.         
(l)    Commonwealth Guaranteed.         
(m)     CIFG Insured.         
(n)    Securities represent underlying bonds transferred to a tender option bond trust 
    in exchange for which the Fund acquired residual interest certificates. These 
    securities serve as collateral in a financing transaction. See Note 1 of the Notes 
    to Financial Statements for details of municipal bonds transferred to tender 
    option bond trusts.         
(o)    Investments in companies considered to be an affiliate of the Fund, for purposes 
    of Section 2(a)(3) of the Investment Company Act of 1940, were as follows: 
   
    Affiliate    Net Activity    Income 
    CMA New Jersey Municipal Money Fund    (9,440,026)    $59,996 
   
 
 
(p)    Represents the current yield as of report date.         

For Fund compliance purposes, the Fund’s industry classifications refer to any
one or more of the industry sub-classifications used by one or more widely
recognized market indexes or ratings group indexes, and/or as defined by Fund
management. This definition may not apply for purposes of this report which
may combine industry sub-classifications for reporting ease.
Effective August 1, 2008, the Fund adopted Financial Accounting Standards Board
Statement of Financial Accounting Standards No. 157, “Fair Value Measurements”
(“FAS 157”). FAS 157 clarifies the definition of fair value, establishes a framework
for measuring fair values and requires additional disclosures about the use of fair
value measurements. Various inputs are used in determining the fair value of
investments, which are as follows:
Level 1 — price quotations in active markets/exchanges for identical
securities
Level 2 — other observable inputs (including, but not limited to: quoted prices
for similar assets or liabilities in markets that are not active, inputs other than
quoted prices that are observable for the assets or liabilities (such as interest
rates, yield curves, volatilities, prepayment speeds, loss severities, credit risks
and default rates) or other market-corroborated inputs)
Level 3 — unobservable inputs based on the best information available in the
circumstance, to the extent observable inputs are not available (including the
Fund’s own assumption used in determining the fair value of investments)
The inputs or methodology used for valuing securities are not necessarily an in-
dication of the risk associated with investing in those securities. For information
about the Fund’s policy regarding valuation of investments and other significant
accounting policies, please refer to Note 1 of the Notes to Financial Statements.
The following table summarizes the inputs used as of January 31, 2009 in deter-
mining the fair valuation of the Fund’s investments:

Valuation    Investments in 
Inputs    Securities 
    Assets 
Level 1    $ 310,880 
Level 2    482,080,752 
Level 3     
Total    $ 482,391,632 

See Notes to Financial Statements.

SEMI-ANNUAL REPORT JANUARY 31, 2009 13


Schedule of Investments January 31, 2009 (Unaudited)    BlackRock MuniYield Insured Investment Fund (MFT) 
                    (Percentages shown are based on Net Assets) 
        Par                    Par     
Municipal Bonds        (000)    Value    Municipal Bonds        (000)    Value 
 
     District of Columbia — 0.8%                    Florida (continued)             
Utilities — Water & Sewer — 0.8%                Hospitals/Healthcare (concluded)             
District of Columbia, Water and Sewer Authority, Public            Jacksonville, Florida, Health Facilities Authority, Hospital         
 Utility Revenue Refunding Bonds, Senior Lien,                 Revenue Bonds (Baptist Medical Center Project),             
 Series A, 6%, 10/01/35    $ 750     $ 784,635     5%, 8/15/37 (c)    $ 2,875     $ 2,519,794 
                Lee Memorial Health System, Florida, Hospital Revenue         
                 Bonds, Series A, 5%, 4/01/32 (a)        2,000    1,466,360 
     Florida — 122.6%                Orange County, Florida, Health Facilities Authority,             
County/City/Special District/School/District — 9.2%             Hospital Revenue Bonds (Orlando Regional             
Lee County, Florida, Capital Revenue Bonds,                 Healthcare), 6%, 12/01/12 (e)        1,835    2,137,940 
 5.25%, 10/01/23 (a)        2,285    2,353,024    Orange County, Florida, Health Facilities Authority,             
Leesburg, Florida, Capital Improvement Revenue                 Hospital Revenue Refunding Bonds (Orlando             
 Bonds, 5.25%, 10/01/34 (d)(f)        1,000    930,720     Regional Healthcare), Series B, 5.25%, 12/01/29 (c)    1,450    1,342,599 
Miami-Dade County, Florida, Special Obligation                South Lake County, Florida, Hospital District Revenue         
 Revenue Bonds, Sub-Series A (f)(g):                 Bonds (South Lake Hospital Inc.), 5.80%, 10/01/34    1,000    800,780 
     5.184%, 10/01/31        4,375    893,813                    8,966,983 
     5.20%, 10/01/33        5,735    1,002,593    Housing — 2.5%             
Orange County, Florida, Sales Tax Revenue Refunding            Florida HFA, Housing Revenue Bonds (Brittany             
 Bonds, Series A, 5.125%, 1/01/23 (d)(f)        1,000    1,012,510     Rosemont Apartments), AMT, Series C-1,             
Palm Beach County, Florida, Criminal Justice Facilities             6.75%, 8/01/14 (a)        845    846,352 
 Revenue Bonds, 7.20%, 6/01/15 (d)(f)        1,500    1,876,920    Florida Housing Finance Corporation, Homeowner             
Saint Johns County, Florida, Sales Tax Revenue Bonds,             Mortgage Revenue Bonds, AMT, Series 11,             
 Series A, 5.25%, 10/01/31 (a)        1,400    1,349,586     5.95%, 1/01/32 (c)        1,520    1,479,173 
            9,419,166    Florida Housing Finance Corporation, Homeowner             
Education — 31.5%                 Mortgage Revenue Refunding Bonds, AMT, Series 4,         
Alachua County, Florida, School Board, COP,                 6.25%, 7/01/22 (c)        265    273,757 
 5.25%, 7/01/29 (a)        1,300    1,171,898                    2,599,282 
Broward County, Florida, Educational Facilities Authority            IDA/PCR/Resource Recovery — 13.2%             
 Revenue Bonds (Nova Southeastern University),                Hillsborough County, Florida, IDA, PCR, Refunding             
 5%, 4/01/31 (b)        1,720    1,620,962     (Tampa Electric Company Project), Series B,             
Broward County, Florida, School Board, COP, Series A,             5.15%, 9/01/25        500    494,620 
 5.25%, 7/01/33 (c)        2,000    1,889,580    Jacksonville, Florida, Economic Development             
Florida State Board of Education, Lottery Revenue                 Commission, IDR (Metropolitan Parking Solutions             
 Bonds, Series A, 6%, 7/01/10 (d)(e)        6,190    6,710,084     Project), AMT, 5.50%, 10/01/30 (h)        1,140    808,089 
Hillsborough County, Florida, School Board, COP,                Miami-Dade County, Florida, IDA, IDR (BAC Funding             
 5%, 7/01/29 (f)        1,000    921,790     Corporation Project), Series A, 5.375%, 10/01/30 (a)    1,655    1,645,434 
Miami-Dade County, Florida, School Board, COP,                Miami-Dade County, Florida, Solid Waste System             
 Refunding, Series B, 5.25%, 5/01/30 (b)        1,415    1,362,277     Revenue Bonds, 5.25%, 10/01/30 (f)        1,865    1,810,840 
Orange County, Florida, Educational Facilities Authority,            Orange County, Florida, Tourist Development, Tax             
 Educational Facilities Revenue Refunding Bonds                 Revenue Refunding Bonds, 5%, 10/01/29 (a)        2,190    1,946,603 
 (Rollins College Project), 5.50%, 12/01/32 (a)        4,765    4,545,762    Orlando, Florida, Senior Tourist Development Tax             
Palm Beach County, Florida, School Board, COP:                 Revenue Bonds (6th Cent Contract Payments),             
     Refunding, Series D, 5.25%, 8/01/21 (c)        2,000    2,072,360     Series A, 5.25%, 11/01/38 (b)        2,000    1,866,160 
     Series A, 6%, 8/01/10 (d)(e)        5,000    5,430,350    Osceola County, Florida, Tourist Development Tax             
     Series A, 5%, 8/01/31 (c)        1,300    1,197,781     Revenue Bonds, Series A, 5.50%, 10/01/27 (d)(f)    1,100    1,067,451 
Santa Rosa County, Florida, School Board, COP,                Village Center Community Development District,             
 Refunding, Series 2, 5.25%, 2/01/26 (d)(f)        2,000    1,880,020     Florida, Recreational Revenue Bonds, Series A (f):             
University of Central Florida Athletics Association Inc.,                5.375%, 11/01/34        1,640    1,417,944 
 COP, Series A, 5.25%, 10/01/34 (d)(f)        2,280    1,717,798        5.125%, 11/01/36        1,000    824,200 
University of Central Florida, COP (UCF Convocation                Volusia County, Florida, IDA, Student Housing Revenue         
 Center), Series A, 5%, 10/01/35 (d)(f)        2,795    1,774,937     Bonds (Stetson University Project), Series A (i):             
            32,295,599        5%, 6/01/25        1,000    853,000 
Hospitals/Healthcare — 8.7%                    5%, 6/01/35        1,000    753,140 
Jacksonville, Florida, Economic Development                                13,487,481 
 Commission, Health Care Facilities Revenue                                 
 Bonds (Mayo Clinic-Jacksonville), Series B,                                 
 5.50%, 11/15/36 (f)        750    699,510                     

See Notes to Financial Statements.

14 SEMI-ANNUAL REPORT JANUARY 31, 2009


Schedule of Investments (continued)    BlackRock MuniYield Insured Investment Fund (MFT) 
                (Percentages shown are based on Net Assets) 
        Par                Par     
Municipal Bonds        (000)    Value    Municipal Bonds        (000)    Value 
 
     Florida (continued)                     Florida (concluded)             
Special Tax — 1.4%                Utilities — Irrigation, Resource Recovery, Solid Waste         
Jacksonville, Florida, Guaranteed Entitlement                & Other — 9.2%             
 Revenue Refunding and Improvement Bonds,                Boynton Beach, Florida, Utility System Revenue             
 5.25%, 10/01/32 (d)(f)    $ 1,455     $ 1,412,674     Refunding Bonds, 6.25%, 11/01/20 (d)(j)    $ 700     $ 869,155 
Transportation — 35.1%                Emerald Coast, Florida, Utilities Authority, System             
Deltona, Florida, Transportation Capital Improvement             Revenue Bonds, 5.25%, 1/01/36 (d)(f)        1,000    897,950 
 Revenue Bonds, 5.125%, 10/01/26 (f)        1,000    940,650    Saint Johns County, Florida, Ponte Vedra Utility System         
Florida State Turnpike Authority, Turnpike Revenue                 Revenue Bonds, 5%, 10/01/31 (c):        2,425    2,262,840 
 Bonds (Department of Transportation), Series B,                Village Center Community Development District, Florida,         
 5%, 7/01/30        1,860    1,777,509     Utility Revenue Bonds (f):             
Hillsborough County, Florida, Aviation Authority Revenue                 5.25%, 10/01/23        2,585    2,634,244 
 Bonds, AMT, Series A, 5.50%, 10/01/38 (b)        2,505    2,128,073         5.125%, 10/01/28        3,030    2,719,546 
Hillsborough County, Florida, Aviation Authority,                            9,383,735 
 Revenue Refunding Bonds, AMT, Series C,                Utilities — Water & Sewer — 4.4%             
 5.75%, 10/01/26 (b)        1,000    942,790    Florida State Governmental Utility Authority,             
Jacksonville, Florida, Port Authority Revenue Bonds,                 Utility Revenue Bonds (Lehigh Utility System),             
 AMT, 6%, 11/01/38 (b)        2,550    2,329,910     5.125%, 10/01/33 (a)        1,000    931,760 
Jacksonville, Florida, Port Authority, Seaport Revenue            Miami Beach, Florida, Water and Sewer Revenue             
 Bonds, AMT, 5.625%, 11/01/26 (f)        1,225    1,082,361     Bonds, 5.75%, 9/01/25 (a)        2,000    2,064,860 
Lee County, Florida, Airport Revenue Bonds, AMT,                Panama City, Florida, Water and Sewer Revenue Bonds,         
 Series A, 6%, 10/01/29 (c)        1,000    923,220     Series B, 5.25%, 10/01/22 (f)        1,500    1,562,505 
Miami-Dade County, Florida, Aviation Revenue Bonds                         
 AMT, Series A:                            4,559,125 
     5%, 10/01/33 (c)        6,300    5,041,071    Total Municipal Bonds in Florida            125,721,658 
     (Miami International Airport), 6%, 10/01/24 (d)(f)    5,000    4,798,650                 
Miami-Dade County, Florida, Aviation Revenue                             
 Refunding Bonds (Miami International Airport),                     Illinois — 3.0%             
 AMT Series A (c):                Transportation — 1.5%             
     5.25%, 10/01/41        1,200    969,948    Chicago, Illinois, Transit Authority, Capital Grant             
     5.50%, 10/01/41        2,400    2,019,000     Receipts Revenue Bonds (Federal Transit             
Miami-Dade County, Florida, Expressway Authority, Toll             Administration Section 5309 Formula Funds),             
 System Revenue Bonds, Series B (d)(f):                 Series A, 6%, 6/01/26 (b)        1,400    1,532,230 
     5.25%, 7/01/27        1,000    1,000,420                 
     5%, 7/01/33        2,400    2,197,584    Utilities — Electric & Gas — 1.5%             
Orlando-Orange County Expressway Authority, Florida,            Illinois Municipal Electric Agency, Power Supply             
 Expressway Revenue Bonds, Series B (a):                 Revenue Bonds, Series A, 5.25%, 2/01/28 (d)(f)        1,565    1,548,317 
     5%, 7/01/30        3,950    3,712,526    Total Municipal Bonds in Illinois            3,080,547 
     5%, 7/01/35        6,815    6,167,371                 
            36,031,083         Louisiana — 0.5%             
Utilities — Electric & Gas — 7.4%                             
Daytona Beach, Florida, Utility System Revenue                Transportation — 0.5%             
 Refunding Bonds, Series B, 5%, 11/15/27 (d)(f)        1,000    825,290    New Orleans, Louisiana, Aviation Board Revenue             
Lakeland, Florida, Electric and Water Revenue                 Refunding Bonds (b):             
 Refunding Bonds, Series A, 5%, 10/01/28 (f)        2,000    1,917,680         Series A-1, 6%, 1/01/23        375    376,646 
Martin County, Florida, Utilities System Revenue Bonds,                 Series A-2, 6%, 1/01/23        160    161,658 
 5.125%, 10/01/33 (a)        1,000    919,300    Total Municipal Bonds in Louisiana            538,304 
Polk County, Florida, Utility System Revenue Bonds,                             
 5.25%, 10/01/22 (d)(f)        1,000    1,016,050                 
Port St. Lucie, Florida, Utility Revenue Bonds,                     Michigan — 2.2%             
 5.25%, 9/01/24 (f)        1,055    1,066,130    Hospitals/Healthcare — 1.2%             
Saint Johns County, Florida, Ponte Vedra Utility System            Royal Oak, Michigan, Hospital Finance Authority,             
 Revenue Bonds, 5%, 10/01/35 (c):        1,000    917,340     Hospital Revenue Refunding Bonds (William             
Saint Lucie, Florida, West Services District, Utility                 Beaumont Hospital), 8.25%, 9/01/39        1,265    1,292,526 
 Revenue Bonds, 5.25%, 10/01/34 (f)        1,000    904,740                 
            7,566,530                 

See Notes to Financial Statements.

SEMI-ANNUAL REPORT

JANUARY 31, 2009

15


Schedule of Investments (continued)    BlackRock MuniYield Insured Investment Fund (MFT) 
                (Percentages shown are based on Net Assets) 
        Par                Par     
Municipal Bonds        (000)    Value    Municipal Bonds        (000)    Value 
     Michigan (concluded)                     Virginia — 1.2%             
Utilities — Water & Sewer — 1.0%                Education — 1.2%             
Detroit, Michigan, Sewage Disposal System, Second            Virginia State Public School Authority, Special             
 Lien Revenue Refunding Bonds, Series E,                 Obligation School Financing Bonds (Fluvanna             
 5.75%, 7/01/31 (d)(k)    $ 1,000    $ 1,026,270     County), 6.50%, 12/01/35    $ 1,100     $ 1,214,279 
Total Municipal Bonds in Michigan            2,318,796                 
                     Puerto Rico — 0.8%             
     Minnesota — 3.1%                Lease Obligations — 0.8%             
                Puerto Rico Public Buildings Authority, Government             
Hospitals/Healthcare — 3.1%                 Facilities Revenue Refunding Bonds, Series I,             
Minneapolis, Minnesota, Health Care System, Revenue             5%, 7/01/36 (l)        1,000    791,000 
 Refunding Bonds (Fairview Health Services),                             
 Series B, 6.50%, 11/15/38 (b)        3,000    3,168,660    Total Municipal Bonds — 142.7%            146,370,787 
     Nevada — 2.1%                             
                Municipal Bonds Transferred to             
County/City/Special District/School/District — 2.1%            Tender Option Bond Trusts (m)             
Clark County, Nevada, Water Reclamation District,                             
 Limited Tax, GO, 6%, 7/01/38        2,010    2,129,997         Florida — 17.3%             
                County/City/Special District/School/District — 2.2%         
     New Jersey — 1.0%                Jacksonville, Florida, Sales Tax Revenue Bonds,             
IDA/PCR/Resource Recovery — 1.0%                 5%, 10/01/27 (f)        1,320    1,310,417 
New Jersey EDA, School Facilities Construction Revenue            Manatee County, Florida, HFA, Homeowner Revenue             
 Bonds, Series Z, 6%, 12/15/34 (b)        1,000    1,043,830     Bonds, AMT, Series A, 5.9, 9/01/40 (n)(o)(p)        1,011    1,000,532 
                            2,310,949 
     New York — 0.9%                Hospitals/Healthcare — 12.0%             
                Miami-Dade County, Florida, Health Facilities Authority,         
Education — 0.9%                 Hospital Revenue Refunding Bonds (Miami Children’s         
New York City, New York, City Transitional Finance                 Hospital), Series A, 5.625%, 8/15/18 (a)        6,960    7,756,990 
 Authority, Building Aid Revenue Bonds, Series S-3,            South Broward, Florida, Hospital District, Hospital             
 5.25%, 1/15/39        1,000    953,600     Revenue Bonds, 5.625%, 5/01/32 (f)        4,000    4,581,960 
                            12,338,950 
     Texas — 4.5%                Housing — 1.9%             
                Lee County, Florida, HFA, S/F Mortgage Revenue             
Education — 1.1%                 Bonds (Multi-County Program), AMT, Series A-2,             
Tarrant County, Texas, Cultural Education Facilities                 6%, 9/01/40 (n)(o)(p)        1,800    1,923,066 
 Financing Corporation, Revenue Refunding Bonds                             
 (CHRISTUS Health), Series A, 6.50%, 7/01/37 (b)    1,100    1,149,798    Utilities — Electric & Gas — 1.2%             
                Jacksonville Electric Authority, Florida, Saint John’s             
Hospitals/Healthcare — 0.5%                 River Power Park System Revenue Bonds, Issue Three,         
Harris County, Texas, Health Facilities Development                 Series 2, 5%, 10/01/37        1,290    1,183,497 
 Corporation, Hospital Revenue Refunding Bonds                             
 (Memorial Hermann Healthcare System), Series B,            Total Municipal Bonds Transferred to Tender Option         
 7.25%, 12/01/35        500    522,075    Bond Trusts — 17.3%            17,756,462 
Transportation — 2.9%                Total Long-Term Investments             
North Texas Tollway Authority, System Revenue                (Cost — $173,909,298) — 160.0%            164,127,249 
 Refunding Bonds, First Tier:                             
     Series A, 5.75%, 1/01/40        1,500    1,523,970                 
     Series K-1, 5.75%, 1/01/38 (b)        1,400    1,429,638                 
            2,953,608                 
Total Municipal Bonds in Texas            4,625,481                 

See Notes to Financial Statements.

16 SEMI-ANNUAL REPORT

JANUARY 31, 2009


Schedule of Investments (concluded) BlackRock MuniYield Insured Investment Fund (MFT)
(Percentages shown are based on Net Assets)

        Par     
Short-Term Securities    (000)    Value 
    Pennsylvania — 1.8%         
Philadelphia, Pennsylvania, GO, VRDN, Refunding,         
 Series B, 3.75%, 2/05/09 (c)(q)    $ 1,800    $ 1,800,000 
 
        Shares     
    Money Market Funds — 5.4%         
CMA Florida Municipal Money Fund, 0.11% (r)(s)    5,548,510    5,548,510 
Total Short-Term Securities         
(Cost — $7,348,510) — 7.2%        7,348,510 
Total Investments (Cost — $181,257,808*) — 167.2%    171,475,759 
Other Assets Less Liabilities — 1.9%        1,910,744 
Liability for Trust Certificates, Including Interest         
   Expense and Fees Payable — (8.4)%        (8,563,227) 
Preferred Shares, at Redemption Value — (60.7)%        (62,257,607) 
Net Assets Applicable to Common Shares — 100.0%        $102,565,669 
       
   * The cost and unrealized appreciation (depreciation) of investments as of 
    January 31, 2009, as computed for federal income tax purposes, were 
    as follows:         
    Aggregate cost        $ 172,812,151 
    Gross unrealized appreciation        $ 4,526,655 
    Gross unrealized depreciation        (14,353,679) 
    Net unrealized depreciation        $ (9,827,024) 
           
(a)    AMBAC Insured.         
(b)    Assured Guaranty Insured.         
(c)    FSA Insured.         
(d)    FGIC Insured.         
(e)    US government securities, held in escrow, are used to pay interest on this 
    security as well as to retire the bond in full at the date indicated, typically at 
    a premium to par.         
(f)    MBIA Insured.         
(g)    Represents a zero-coupon bond. Rate shown reflects the current yield as of 
    report date.         
(h)    ACA Insured.         
(i)    CIFG Insured.         
(j)    Security is collateralized by Municipal or US Treasury Obligations.     
(k)    BHAC Insured.         
(l)    Commonwealth Guaranteed.         
(m)     Securities represent underlying bonds transferred to a tender option bond trust 
    in exchange for which the Fund acquired residual interest certificates. These 
    securities serve as collateral in a financing transaction. See Note 1 of the Notes 
    to Financial Statements for details of municipal bonds transferred to tender 
    option bond trusts.         
(n)    FHLMC Collateralized.         
(o)    FNMA Collateralized.         
(p)    GNMA Collateralized.         
(q)    Security may have a maturity of more than one year at the time of issuance, but 
    has variable rate and demand features that qualify it as a short-term security. The 
    rate disclosed is as of report date. This rate changes periodically based upon 
    prevailing market rates.         

(r)    Investments in companies considered to be an affiliate of the Fund, for purposes 
    of Section 2(a)(3) of the Investment Company Act of 1940, were as follows: 
   
        Net     
    Affiliate    Activity    Income 
    CMA Florida Municipal Money Fund    (6,863,534)    $36,359 
   
 
 
(s)    Represents the current yield as of report date.         

For Fund compliance purposes, the Fund’s industry classifications refer to any
one or more of the industry sub-classifications used by one or more widely
recognized market indexes or ratings group indexes, and/or as defined by Fund
management. This definition may not apply for purposes of this report which
may combine industry sub-classifications for reporting ease.
Effective August 1, 2008, the Fund adopted Financial Accounting Standards Board
Statement of Financial Accounting Standards No. 157, “Fair Value Measurements”
(“FAS 157”). FAS 157 clarifies the definition of fair value, establishes a framework
for measuring fair values and requires additional disclosures about the use of fair
value measurements. Various inputs are used in determining the fair value of
investments, which are as follows:
Level 1 — price quotations in active markets/exchanges for identical
securities
Level 2 — other observable inputs (including, but not limited to: quoted prices
for similar assets or liabilities in markets that are not active, inputs other than
quoted prices that are observable for the assets or liabilities (such as interest
rates, yield curves, volatilities, prepayment speeds, loss severities, credit risks
and default rates) or other market-corroborated inputs)
Level 3 — unobservable inputs based on the best information available in the
circumstance, to the extent observable inputs are not available (including the
Fund’s own assumption used in determining the fair value of investments)
The inputs or methodology used for valuing securities are not necessarily an in-
dication of the risk associated with investing in those securities. For information
about the Fund’s policy regarding valuation of investments and other significant
accounting policies, please refer to Note 1 of the Notes to Financial Statements.
The following table summarizes the inputs used as of January 31, 2009 in deter-
mining the fair valuation of the Fund’s investments:

Valuation    Investments in 
Inputs    Securities 
    Assets 
Level 1    $ 5,548,510 
Level 2    165,927,249 
Level 3     
Total    $ 171,475,759 

See Notes to Financial Statements.

SEMI-ANNUAL REPORT JANUARY 31, 2009 17


Schedule of Investments January 31, 2009 (Unaudited)    BlackRock MuniYield Michigan Insured Fund, Inc. (MIY) 
                (Percentages shown are based on Net Assets) 
    Par                    Par     
Municipal Bonds    (000)    Value    Municipal Bonds        (000)    Value 
 
     Michigan — 140.5%                Michigan (continued)             
County/City/Special District/School/District — 30.6%        County/City/Special District/School/District (concluded)         
Adrian, Michigan, City School District, GO,            Thornapple Kellogg School District, Michigan, GO,             
 5%, 5/01/14 (a)(e)    $ 3,600    $  4,191,336     Refunding, 5%, 5/01/32 (d)    $ 2,500    $  2,452,625 
Birmingham, Michigan, City School District, School        West Bloomfield, Michigan, School District, GO,             
 Building and Site, GO, 5%, 11/01/33 (e)    1,000    979,070     Refunding (b)(d):             
Central Montcalm, Michigan, Public Schools, GO,            5.50%, 5/01/17        1,710    1,875,973 
 5.90%, 5/01/09 (a)(d)    1,000    1,013,770        5.50%, 5/01/18        1,225    1,323,919 
Detroit, Michigan, City School District, GO (School        Zeeland, Michigan, Public Schools, School Building             
 Building and Site Improvement):             and Site, GO, 5%, 5/01/29 (d)        1,600    1,577,824 
     Refunding, Series A, 5%, 5/01/21 (e)    3,000    3,080,250                    75,168,523 
     Series A, 5.375%, 5/01/13 (a)(b)    2,300    2,667,861                     
     Series B, 5%, 5/01/28 (b)    3,100    2,903,087    Education — 7.1%             
Eaton Rapids, Michigan, Public Schools, School            Eastern Michigan University, General Revenue             
 Building and Site, GO (e):             Refunding Bonds (c):             
     5.25%, 5/01/20    1,325    1,437,506        6%, 6/01/10 (a)        590    637,294 
     5.25%, 5/01/21    1,675    1,790,592        6%, 6/01/20        435    454,371 
Frankenmuth, Michigan, School District, GO,            Eastern Michigan University Revenue Bonds, Series B,         
 5.75%, 5/01/10 (a)(b)    1,000    1,063,220     5.60%, 6/01/10 (a)(b)        1,500    1,595,955 
Gibraltar, Michigan, School District, GO (School            Grand Valley State University, Michigan, Revenue Bonds,         
 Building and Site) (b):             5.50%, 2/01/18 (b)(d)        2,070    2,281,595 
     5%, 5/01/14 (a)    2,940    3,422,924    Michigan Higher Education Facilities Authority, Limited         
     5%, 5/01/28    710    710,270     Obligation Revenue Bonds (Hillsdale College Project),         
Grand Blanc, Michigan, Community Schools, GO,             5%, 3/01/35        1,875    1,541,981 
 5.625%, 5/01/20 (b)(d)    1,100    1,175,691    Michigan Higher Education Facilities Authority, Limited         
Gull Lake, Michigan, Community School District, School         Obligation Revenue Refunding Bonds:             
 Building and Site, GO, 5%, 5/01/14 (a)(e)    5,625    6,548,963        (College for Creative Studies), 5.85%, 6/01/12 (a)    1,235    1,404,393 
Harper Woods, Michigan, City School District, School            (College for Creative Studies), 5.90%, 6/01/12 (a)    1,145    1,303,892 
 Building and Site, GO, Refunding (b):                (Hope College), Series A, 5.90%, 4/01/32        2,250    1,840,005 
     5%, 5/01/14 (a)    4,345    5,058,710    Michigan Higher Education Student Loan Authority,             
     5%, 5/01/34    430    416,778     Student Loan Revenue Bonds, AMT, Series XVII-Q,             
Hartland, Michigan, Consolidated School District, GO,         5%, 3/01/31 (c)        3,000    2,055,060 
 6%, 5/01/10 (a)(b)    6,825    7,277,703    Michigan Municipal Bond Authority Revenue Bonds             
Jenison, Michigan, Public Schools, School Building and         (Local Government Loan Program), Group A,             
 Site, GO, 5.50%, 5/01/19 (b)(d)    1,575    1,688,495     5.50%, 11/01/20 (c)        1,065    1,089,921 
Lansing, Michigan, Building Authority, GO, Series A,        Saginaw Valley State University, Michigan, General             
 5.375%, 6/01/13 (a)(d)    1,510    1,756,100     Revenue Refunding Bonds, 5%, 7/01/24 (b)(d)        2,100    2,066,673 
Montrose Township, Michigan, School District, GO,        Waverly, Michigan, Community School, GO,             
 6.20%, 5/01/17 (d)    1,000    1,223,170     5.50%, 5/01/10 (a)(b)        1,100    1,163,404 
Norway Vulcan, Michigan, Area Schools, GO,                            17,434,544 
 5.90%, 5/01/09 (a)(b)    1,100    1,115,202    Hospitals/Healthcare — 22.5%             
Oak Park, Michigan, Street Improvement, GO,            Dickinson County, Michigan, Healthcare             
 5%, 5/01/30 (d)    500    470,045     System, Hospital Revenue Refunding Bonds,             
Orchard View, Michigan, Schools, School Building and         5.80%, 11/01/24 (h)        3,100    2,492,462 
 Site, GO, 5%, 11/01/13 (a)(d)    5,320    6,166,465    Flint, Michigan, Hospital Building Authority, Revenue             
Pennfield, Michigan, School District, School Building         Refunding Bonds (Hurley Medical Center), Series A (h):         
 and Site, GO, 5%, 5/01/14 (a)(b)    1,370    1,586,816        5.375%, 7/01/20        615    451,189 
Reed, Michigan, City Public Schools, School Building            6%, 7/01/20        1,375    1,073,559 
 and Site, GO, 5%, 5/01/14 (a)(e)    1,425    1,659,071    Kent, Michigan, Hospital Finance Authority, Hospital             
South Haven, Michigan, Public Schools, GO,             Revenue Refunding Bonds (Butterworth Hospital),             
 5%, 5/01/13 (e)    1,350    1,545,129     Series A, 7.25%, 1/15/13 (d)        2,685    2,983,357 
Southfield, Michigan, Library Building Authority, GO,        Kent, Michigan, Hospital Finance Authority             
 5.50%, 5/01/10 (a)(d)    1,300    1,378,143     Revenue Bonds (Spectrum Health), Series A,             
Southfield, Michigan, Public Schools, School Building         5.50%, 7/15/11 (a)(d)        3,000    3,331,380 
 and Site, GO, Series A, 5%, 5/01/14 (a)(e)    3,500    4,069,170    Michigan State Hospital Finance Authority, Hospital             
Sparta, Michigan, Area Schools, School Building and         Revenue Bonds (Mid-Michigan Obligation Group),             
 Site, GO, 5%, 5/01/14 (a)(b)    1,325    1,542,645     Series A, 5.50%, 4/15/18 (c)        2,530    2,550,974 

See Notes to Financial Statements.

18 SEMI-ANNUAL REPORT

JANUARY 31, 2009


Schedule of Investments (continued)    BlackRock MuniYield Michigan Insured Fund, Inc. (MIY) 
            (Percentages shown are based on Net Assets) 
    Par                Par     
Municipal Bonds    (000)    Value    Municipal Bonds        (000)    Value 
 
     Michigan (continued)                 Michigan (continued)             
Hospitals/Healthcare (concluded)            IDA/PCR/Resource Recovery — 12.6%             
Michigan State Hospital Finance Authority, Hospital            Delta County, Michigan, Economic Development             
 Revenue Refunding Bonds:             Corporation, Environmental Improvement Revenue             
     (Crittenton Hospital), Series A, 5.625%, 3/01/27     $ 2,200     $ 1,856,404     Refunding Bonds (Mead Westvaco-Escanaba), AMT,         
     (Oakwood Obligated Group), Series A,             Series B, 6.45%, 4/15/12 (a)    $ 1,500    $ 1,726,844 
     5%, 7/15/25    4,100    3,351,012    Dickinson County, Michigan, Economic Development         
     (Oakwood Obligated Group), Series A,             Corporation, Environmental Improvement Revenue             
     5%, 7/15/37    630    448,636     Refunding Bonds (International Paper Company             
     (Sparrow Obligated Group), 5%, 11/15/31    3,100    2,283,460     Project), Series A, 5.75%, 6/01/16        3,900    3,277,599 
Michigan State Hospital Finance Authority            Michigan State Strategic Fund, Limited Obligation             
 Revenue Bonds:             Revenue Refunding Bonds (Detroit Edison             
     (McLaren Health Care Corporation), Series C,             Company Pollution Control Project), AMT Series A,             
     5%, 8/01/35    1,000    712,260     5.55%, 9/01/29 (d)        10,250    8,457,480 
     (Mid-Michigan Obligor Group), Series A,            Monroe County, Michigan, Economic Development             
     5%, 4/15/36    1,750    1,326,728     Corporation, Limited Obligation Revenue Refunding         
     (Trinity Health Credit Group), Series A,             Bonds (Detroit Edison Co. Project), Series AA,             
     6.25%, 12/01/28    930    947,679     6.95%, 9/01/22 (b)(d)        15,000    17,466,750 
     (Trinity Health Credit Group), Series A,                        30,928,673 
     6.50%, 12/01/33    1,000    1,024,100                 
Michigan State Hospital Finance Authority, Revenue            Lease Obligations — 14.4%             
 Refunding Bonds:            Grand Rapids, Michigan, Building Authority Revenue             
     (Ascension Health Credit), Series A,             Bonds, Series A, 5.50%, 10/01/12 (a)(c)        1,035    1,187,849 
     6.25%, 11/15/09 (a)(d)    2,500    2,637,700    Michigan State Building Authority, Revenue Refunding         
     (Henry Ford Health System), Series A,             Bonds (Facilities Program):             
     5.25%, 11/15/46    2,500    1,623,700         Series I, 5.50%, 10/15/10 (e)        7,250    7,716,030 
     (McLaren Health Care Corporation),                 Series I, 5.50%, 10/15/11 (e)        15,030    16,437,560 
     5.75%, 5/15/38    4,500    3,606,480         Series I, 5.50%, 10/15/18 (d)        2,500    2,607,800 
     (Saint John Hospital), Series A,                 Series I, 6.25%, 10/15/38        3,900    4,076,163 
     6%, 5/15/13 (c)(f)    3,000    3,078,120         Series II, 5%, 10/15/29 (d)        3,500    3,172,505 
     (Trinity Health Credit Group), Series A,                        35,197,907 
     6%, 12/01/20    2,200    2,272,930                 
            Special Tax — 0.7%             
     (Trinity Health Credit Group), Series A,                         
            Wayne Charter County, Michigan, Detroit Metropolitan         
     6%, 12/01/27 (c)    6,400    6,449,024                 
             Airport, GO, Airport Hotel, Series A, 5%, 12/01/30 (d)    1,750    1,643,670 
     (Trinity Health Credit Group), Series C,                         
     5.375%, 12/01/23    1,000    1,003,530    State — 1.6%             
     (Trinity Health Credit Group), Series C,            Michigan Higher Education Student Loan Authority,             
     5.375%, 12/01/30    3,755    3,475,403     Student Loan Revenue Bonds, AMT, Series XVII-B,             
     (Trinity Health Credit Group), Series D,             5.40%, 6/01/18 (c)        2,500    2,243,175 
     5%, 8/15/34    3,100    2,654,251    Michigan State, COP, 5.515%, 6/01/22 (c)(f)(g)        3,000    1,744,230 
Royal Oak, Michigan, Hospital Finance Authority,                        3,987,405 
 Hospital Revenue Refunding Bonds (William                         
 Beaumont Hospital), 8.25%, 9/01/39    1,000    1,021,760    Transportation — 17.2%             
Saginaw, Michigan, Hospital Finance Authority, Revenue            Wayne Charter County, Michigan, Airport Revenue             
 Refunding Bonds (Covenant Medical Center),             Bonds (Detroit Metropolitan Wayne County), AMT,             
 Series E, 5.625%, 7/01/13 (d)    2,500    2,540,525     Series A, 5.375%, 12/01/15 (d)        10,660    10,747,732 
            Wayne County, Michigan, Airport Authority Revenue             
        55,196,623     Bonds (Detroit Metropolitan Wayne County Airport),         
Housing — 2.3%             AMT (d):             
Eastern Michigan University Revenue Bonds, Series B,                 5.25%, 12/01/25        7,525    6,598,071 
 5.625%, 6/01/10 (a)(b)    1,310    1,394,233         5.25%, 12/01/26        6,300    5,475,015 
Michigan State, HDA, Limited Obligation M/F Housing                 5%, 12/01/34        9,160    7,092,130 
     Revenue Bonds, AMT (i):            Wayne County, Michigan, Airport Authority, Revenue             
     (Deaconess Towers Apartments), 5.25%, 2/20/48    1,000    842,180     Refunding Bonds, AMT (j):             
     (Williams Pavilion Apartments), 4.75%, 4/20/37    4,050    3,168,801         5.75%, 12/01/25        4,000    3,793,160 
Michigan State, HDA, Rental Housing Revenue Bonds,                 5.75%, 12/01/26        1,000    941,480 
 AMT, Series A, 5.30%, 10/01/37 (d)    200    173,598         5.375%, 12/01/32        8,700    7,400,220 
        5,578,812                42,047,808 

  See Notes to Financial Statements.

SEMI-ANNUAL REPORT

JANUARY 31, 2009

19


Schedule of Investments (continued)    BlackRock MuniYield Michigan Insured Fund, Inc. (MIY) 
            (Percentages shown are based on Net Assets) 
    Par            Par     
Municipal Bonds    (000)    Value    Municipal Bonds    (000)    Value 
 
     Michigan (concluded)                 Puerto Rico (concluded)         
Utilities — Electric & Gas — 10.1%            Transportation — 1.6%         
Michigan State Strategic Fund, Limited Obligation            Puerto Rico Commonwealth Highway and         
 Revenue Refunding Bonds (Detroit Edison             Transportation Authority, Highway Revenue         
 Company Pollution Control Project), Series AA,             Refunding Bonds, Series CC, 5.50%, 7/01/31 (j)    $ 4,000    $ 4,035,840 
 6.95%, 5/01/11 (b)(d)    $ 6,000    $ 6,473,760    Total Municipal Bonds in Puerto Rico        10,594,140 
Saint Clair County, Michigan, Economic Revenue                     
 Refunding Bonds (Detroit Edison Co. Project),            Total Municipal Bonds — 144.8%        355,035,774 
 Series AA, 6.40%, 8/01/24 (c)    17,800    18,201,212             
        24,674,972             
Utilities — Water & Sewer — 21.4%            Municipal Bonds Transferred to         
Detroit, Michigan, Water Supply System Revenue            Tender Option Bond Trusts (l)         
 Bonds, Senior Lien, Series A:                     
     5.875%, 1/01/10 (a)(b)    1,250    1,323,274         Michigan —12.3%         
     5.75%, 7/01/11 (a)(b)    7,250    8,069,540             
     5%, 7/01/13 (a)(d)    3,750    4,279,837    County/City/Special District/School/District — 7.5%     
     5%, 7/01/25 (e)    4,000    3,648,040    Lakewood, Michigan, Public Schools, School Building         
     5%, 7/01/34 (d)    6,900    5,605,904     and Site, GO, 5%, 5/01/37 (e)    6,775    6,580,443 
Detroit, Michigan, Water Supply System Revenue            Portage, Michigan, Public Schools, School Building and     
 Bonds, Second Lien, Series B (d):             Site, GO, 5%, 5/01/31 (e)    4,650    4,582,110 
     5%, 7/01/13 (a)    1,550    1,768,998    Saginaw Valley State University, Michigan, Revenue         
     5%, 7/01/34    2,420    1,966,128     Refunding Bonds, 5%, 7/01/31 (e)    7,500    7,206,525 
Detroit, Michigan, Water Supply System Revenue                    18,369,078 
 Bonds, Series B, 5.25%, 7/01/13 (a)(d)    11,790    13,580,783    Education — 4.8%         
Detroit, Michigan, Water Supply System, Revenue            Wayne State University, Michigan, University Revenue         
 Refunding Bonds:             Refunding Bonds, 5%, 11/15/35 (e)    12,207    11,909,878 
     6.25%, 7/01/12 (b)(f)    1,180    1,279,852             
     Second Lien, Series C, 5%, 7/01/29 (e)    10,570    9,078,890    Total Municipal Bonds Transferred to Tender Option         
Muskegon Heights, Michigan, Water System Revenue            Bond Trusts — 12.3%        30,278,956 
 Bonds, Series A, 5.625%, 11/01/10 (a)(d)    1,830    1,981,451    Total Long-Term Investments         
        52,582,697    (Cost — $394,972,718) — 157.1%        385,314,730 
Total Municipal Bonds in Michigan        344,441,634             
     Puerto Rico — 4.3%            Short-Term Securities    Shares     
Housing — 0.8%            Money Market Funds — 6.9%         
Puerto Rico Housing Financing Authority, Capital            CMA Michigan Municipal Money Fund,         
 Funding Program, Subordinate Revenue Refunding             0.26% (m)(n)    16,825,573    16,825,573 
 Bonds, 5.125%, 12/01/27    2,000    1,963,140    Total Short-Term Securities         
Lease Obligations — 1.4%            (Cost — $16,825,573) — 6.9%        16,825,573 
Puerto Rico Public Buildings Authority, Government            Total Investments (Cost — $411,798,291*) — 164.0%    402,140,303 
 Facilities Revenue Refunding Bonds, Series M-3,            Other Assets Less Liabilities — 1.6%        3,989,225 
 6%, 7/01/27 (d)(k)    2,100    1,979,460    Liability for Trust Certificates, Including Interest         
Puerto Rico Sales Tax Financing Corporation,               Expense and Fees Payable — (6.6)%        (16,267,495) 
 Sales Tax Revenue Refunding Bonds, Series A,            Preferred Shares, at Redemption Value — (59.0)%        (144,668,870) 
 4.991%, 8/01/46 (d)(g)    20,000    1,470,200    Net Assets Applicable to Common Shares — 100.0%        $245,193,163 
        3,449,660             
               * The cost and unrealized appreciation (depreciation) of investments as of 
State — 0.5%                   January 31, 2009, as computed for federal income tax purposes, were 
Puerto Rico Sales Tax Financing Corporation,                   as follows:         
 Sales Tax Revenue Refunding Bonds, Series A,                     
 5.192%, 8/01/43 (d)(g)    12,500    1,145,500           Aggregate cost        $ 396,056,496 
                   Gross unrealized appreciation        $ 15,787,032 
                   Gross unrealized depreciation        (25,893,225) 
                   Net unrealized depreciation        $ (10,106,193) 

  See Notes to Financial Statements.

20 SEMI-ANNUAL REPORT

JANUARY 31, 2009


Schedule of Investments (concluded)    BlackRock MuniYield Michigan Insured Fund, Inc. (MIY)

(a)    US government securities, held in escrow, are used to pay interest on this 
    security as well as to retire the bond in full at the date indicated, typically at a 
    premium to par.         
(b)    FGIC Insured.         
(c)    AMBAC Insured.         
(d)    MBIA Insured.         
(e)    FSA Insured.         
(f)    Security is collateralized by Municipal or US Treasury Obligations.     
(g)    Represents a zero-coupon bond. Rate shown reflects the current yield as of 
    report date.         
(h)    ACA Insured.         
(i)    GNMA Collateralized.         
(j)    Assured Guaranty Insured.         
(k)    Commonwealth Guaranteed.         
(l)    Securities represent underlying bonds transferred to a tender option bond trust 
    in exchange for which the Fund acquired residual interest certificates. These 
    securities serve as collateral in a financing transaction. See Note 1 of the Notes 
    to Financial Statements for details of municipal bonds transferred to tender 
    option bond trusts.         
(m)     Represents the current yield as of report date.         
(n)    Investments in companies considered to be an affiliate of the Fund, for purposes 
    of Section 2(a)(3) of the Investment Company Act of 1940, were as follows: 
   
        Net     
    Affiliate    Activity    Income 
    CMA Michigan Municipal Money Fund    12,258,040    $60,484 

For Fund compliance purposes, the Fund’s industry classifications refer to any
one or more of the industry sub-classifications used by one or more widely
recognized market indexes or ratings group indexes, and/or as defined by Fund
management. This definition may not apply for purposes of this report which
may combine industry sub-classifications for reporting ease.

Effective August 1, 2008, the Fund adopted Financial Accounting Standards Board
Statement of Financial Accounting Standards No. 157, “Fair Value Measurements”
(“FAS 157”). FAS 157 clarifies the definition of fair value, establishes a framework
for measuring fair values and requires additional disclosures about the use of fair
value measurements. Various inputs are used in determining the fair value of
investments, which are as follows:
Level 1 — price quotations in active markets/exchanges for identical
securities
Level 2 — other observable inputs (including, but not limited to: quoted prices
for similar assets or liabilities in markets that are not active, inputs other than
quoted prices that are observable for the assets or liabilities (such as interest
rates, yield curves, volatilities, prepayment speeds, loss severities, credit risks
and default rates) or other market-corroborated inputs)
Level 3 — unobservable inputs based on the best information available in the
circumstance, to the extent observable inputs are not available (including the
Fund’s own assumption used in determining the fair value of investments)
The inputs or methodology used for valuing securities are not necessarily an in-
dication of the risk associated with investing in those securities. For information
about the Fund’s policy regarding valuation of investments and other significant
accounting policies, please refer to Note 1 of the Notes to Financial Statements.
The following table summarizes the inputs used as of January 31, 2009 in deter-
mining the fair valuation of the Fund’s investments:

Valuation    Investments in 
Inputs    Securities 
    Assets 
Level 1    $ 16,825,573 
Level 2    385,314,730 
Level 3     
Total    $ 402,140,303 

See Notes to Financial Statements.

SEMI-ANNUAL REPORT JANUARY 31, 2009 21


Schedule of Investments January 31, 2009 (Unaudited)    BlackRock MuniYield New Jersey Insured Fund, Inc. (MJI) 
                    (Percentages shown are based on Net Assets) 
        Par                    Par     
Municipal Bonds        (000)    Value    Municipal Bonds        (000)       Value 
     New Jersey — 136.4%                    New Jersey (continued)             
County/City/Special District/School District — 12.6%            Hospitals/Healthcare — 8.7%             
Hopatcong, New Jersey, GO, Sewer Refunding Bonds,            New Jersey Health Care Facilities Financing Authority         
 4.50%, 8/01/33 (a)    $ 750     $ 680,047     Revenue Bonds:             
Hudson County, New Jersey, COP, Refunding,                    (Meridian Health), Series I, 5%, 7/01/38 (e)    $ 750     $ 710,220 
 6.25%, 12/01/16 (b)        1,000    1,127,929        (Somerset Medical Center), 5.50%, 7/01/33        1,125    567,371 
Hudson County, New Jersey, Improvement Authority,                    (South Jersey Hospital System), 6%, 7/01/12 (c)    4,000    4,602,080 
 Capital Appreciation Revenue Bonds, Series A-1,                New Jersey Health Care Facilities Financing Authority,         
 4.486%, 12/15/32 (b)(h)        1,000    221,510     Revenue Refunding Bonds:             
Jackson Township, New Jersey, School District, GO,                    (Atlantic City Medical Center), 5.75%, 7/01/12 (c)    525    593,654 
 5%, 4/15/12 (c)(g)        5,200    5,810,427        (Atlantic City Medical Center), 6.25%, 7/01/12 (c)    290    332,711 
Monmouth County, New Jersey, Improvement Authority,                (Atlantic City Medical Center), 6.25%, 7/01/17    325    336,681 
 Governmental Loan Revenue Refunding Bonds (a):                (Atlantic City Medical Center), 5.75%, 7/01/25    790    771,119 
     5%, 12/01/11 (c)        1,955    2,164,400        (Meridian Health System Obligation Group),             
     5.20%, 12/01/14        240    250,625        5.25%, 7/01/19 (d)        2,250    2,268,090 
     5.25%, 12/01/15        765    799,884                    10,181,926 
     5%, 12/01/17        605    646,551                     
     5%, 12/01/18        545    573,340    Housing — 6.9%             
     5%, 12/01/19        560    585,861    New Jersey State Housing and Mortgage Finance             
Salem County, New Jersey, Improvement Authority                 Agency, Home Buyer Revenue Bonds, AMT, Series CC,         
 Revenue Bonds (Finlaw State Office Building                 5.80%, 10/01/20 (b)        2,640    2,708,508 
 Project) (d):                New Jersey State Housing and Mortgage Finance             
     5.375%, 8/15/28        1,250    1,290,125     Agency, M/F Revenue Bonds, AMT, Series A,             
     5.25%, 8/15/38        700    700,938     4.90%, 11/01/35 (g)        1,000    808,980 
                New Jersey State Housing and Mortgage Finance             
            14,851,637     Agency Revenue Bonds, Series AA, 6.50%, 10/01/38    1,350    1,424,169 
Education — 25.2%                New Jersey State Housing and Mortgage Finance             
New Jersey State Educational Facilities Authority                 Agency, S/F Housing Revenue Refunding Bonds, AMT,         
 Revenue Bonds:                 Series T, 4.70%, 10/01/37        500    388,965 
     (Montclair State University), Series A,                Newark, New Jersey, Housing Authority, Port Authority-         
     5%, 7/01/21 (a)        1,600    1,683,952     Port Newark Marine Terminal, Additional Rent-             
     (Rowan University), Series C, 5%, 7/01/14 (b)(c)    1,185    1,383,950     Backed Revenue Refunding Bonds (City of Newark         
New Jersey State Educational Facilities Authority,                 Redevelopment Projects), 4.375%, 1/01/37 (b)        3,600    2,836,008 
 Revenue Refunding Bonds:                                8,166,630 
     (College of New Jersey), Series D,                                 
     5%, 7/01/35 (d)        3,725    3,649,941    IDA/PCR/Resource Recovery — 18.9%             
     (Montclair State University), Series J,                Gloucester County, New Jersey, Improvement Authority,         
     4.25%, 7/01/30 (b)        2,895    2,391,878     Solid Waste Resource Recovery, Revenue Refunding         
     (Montclair State University), Series L,                 Bonds (Waste Management Inc. Project), Series A,         
     5%, 7/01/14 (b)(c)        3,185    3,719,730     6.85%, 12/01/29        2,000    2,006,660 
     (Ramapo College), Series I, 4.25%, 7/01/31 (a)    1,250    1,032,213    New Jersey EDA, Cigarette Tax Revenue Bonds:             
     (Ramapo College), Series I, 4.25%, 7/01/36 (a)    3,890    3,095,818        5.625%, 6/15/19        1,060    899,961 
     (Rowan University), Series B, 5%, 7/01/26 (e)        2,575    2,639,066        5.75%, 6/15/29 (j)        785    584,189 
     (Stevens Institute of Technology), Series A,                    5.50%, 6/15/31 (j)        225    159,795 
     5%, 7/01/34        1,500    1,059,930        5.75%, 6/15/34 (j)        465    334,935 
     (William Paterson University), Series E,                New Jersey EDA, Motor Vehicle Surcharge Revenue             
     5%, 7/01/21 (f)        1,725    1,747,080     Bonds, Series A (b):             
New Jersey State Higher Education Assistance                    4.949%, 7/01/21 (h)        2,325    1,262,126 
 Authority, Student Loan Revenue Bonds, AMT,                    5%, 7/01/29        3,900    3,630,705 
 Series A, 5.30%, 6/01/17 (a)        3,565    3,601,292        5.25%, 7/01/33        8,500    7,956,170 
University of Medicine and Dentistry of New Jersey,                    5%, 7/01/34        1,765    1,584,846 
 Revenue Bonds, Series A (a):                                 
     5.50%, 12/01/18        570    576,566                     
     5.50%, 12/01/19        1,145    1,150,553                     
     5.50%, 12/01/20        1,130    1,116,090                     
     5.50%, 12/01/21        865    835,209                     
            29,683,268                     

See Notes to Financial Statements.

22 SEMI-ANNUAL REPORT

JANUARY 31, 2009


Schedule of Investments (continued)    BlackRock MuniYield New Jersey Insured Fund, Inc. (MJI) 
            (Percentages shown are based on Net Assets) 
    Par                Par     
Municipal Bonds    (000)    Value    Municipal Bonds        (000)    Value 
     New Jersey (continued)                 New Jersey (concluded)             
IDA/PCR/Resource Recovery (concluded)            Transportation (concluded)             
New Jersey EDA, School Facilities Construction            New Jersey State Turnpike Authority, Turnpike Revenue         
 Revenue Bonds:             Bonds, Series B, 5.926%, 1/01/35 (a)(h)    $ 3,005     $ 1,964,609 
     Series U, 5%, 9/01/37 (a)    $ 1,000     $ 883,860    Port Authority of New York and New Jersey, Consolidated         
     Series Z, 6%, 12/15/34 (e)    1,200    1,252,596     Revenue Bonds, 93rd Series, 6.125%, 6/01/94        1,000    1,081,400 
New Jersey EDA, School Facilities Construction,            Port Authority of New York and New Jersey, Consolidated         
 Revenue Refunding Bonds, Series K,             Revenue Refunding Bonds, AMT:             
 5.25%, 12/15/17 (b)(g)    1,500    1,659,585         138th Series, 4.75%, 12/01/34 (d)        1,000    800,520 
        22,215,428         146th Series, 4.25%, 12/01/32 (d)        5,000    3,612,700 
                 152nd Series, 5.75%, 11/01/30        2,000    1,916,080 
Lease Obligations — 9.0%                 152nd Series, 5.25%, 11/01/35        2,325    2,024,471 
Hudson County, New Jersey, Improvement Authority,                         
 Facility Lease Revenue Refunding Bonds (Hudson                        35,234,475 
 County Lease Project), 5.375%, 10/01/24 (b)(g)    7,500    7,526,100    Utilities — Electric & Gas — 2.8%             
Middlesex County, New Jersey, COP, Refunding,            Union County, New Jersey, Utilities Authority, Senior             
 5%, 8/01/22 (b)    3,000    3,044,190     Lease Revenue Refunding Bonds (Ogden Martin             
        10,570,290     System of Union, Inc.), AMT, Series A (a):             
                 5.375%, 6/01/17        1,590    1,593,816 
State — 10.3%                 5.375%, 6/01/18        1,670    1,670,768 
Garden State Preservation Trust of New Jersey,                         
 Capital Appreciation Revenue Bonds, Series B,                        3,264,584 
 5.114%, 11/01/23 (d)(h)    6,925    3,422,335    Utilities — Water & Sewer — 12.0%             
Garden State Preservation Trust of New Jersey, Open            Jersey City, New Jersey, Sewer Authority, Sewer Revenue         
 Space and Farmland Preservation Revenue Bonds,             Refunding Bonds, 6.25%, 1/01/14 (a)        3,750    4,177,238 
 Series A, 5.80%, 11/01/22 (d)    2,605    2,923,618    New Jersey EDA, Water Facilities Revenue Bonds             
New Jersey Sports and Exposition Authority, Luxury Tax             (New Jersey-American Water Company, Inc. Project),         
 Revenue Refunding Bonds (Convention Center) (b):             AMT, Series A:             
     5.50%, 3/01/21    1,540    1,677,784         5.25%, 11/01/32 (a)        1,000    795,750 
     5.50%, 3/01/22    1,000    1,072,430         6.875%, 11/01/34 (g)        5,070    4,305,850 
Perth Amboy, New Jersey, GO (Convertible CABS),            New Jersey EDA, Water Facilities Revenue Refunding             
 Refunding, 5.139%, 7/01/35 (d)(i)    1,250    941,100     Bonds (United Water of New Jersey, Inc.), Series B,         
Tobacco Settlement Financing Corporation of             4.50%, 11/01/25 (a)        1,000    981,700 
 New Jersey, Asset-Backed Revenue Bonds,            North Hudson Sewage Authority, New Jersey, Sewer             
 7%, 6/01/13 (c)    1,715    2,089,333     Revenue Refunding Bonds, 5.125%, 8/01/20 (b)    1,710    1,839,704 
        12,126,600    Rahway Valley Sewerage Authority, New Jersey, Sewer         
             Revenue Bonds, CABS, Series A (b)(h):             
Transportation — 30.0%                 4.738%, 9/01/26        4,100    1,503,921 
Delaware River Port Authority of Pennsylvania and                 4.384%, 9/01/33        2,350    510,420 
 New Jersey Revenue Bonds, 6%, 1/01/18 (d)    5,000    5,110,600                 
Essex County, New Jersey, Improvement Authority,                        14,114,583 
 Airport Revenue Refunding Bonds, AMT,            Total Municipal Bonds in New Jersey            160,409,421 
 4.75%, 11/01/32 (b)    1,000    759,050                 
Hudson County, New Jersey, Improvement Authority,                 Puerto Rico — 10.8%             
 Parking Revenue Bonds (Harrison Parking Facility                         
 Project), Series C, 5.375%, 1/01/44 (e)    1,400    1,388,800    Hospitals/Healthcare — 3.4%             
Morristown, New Jersey, Parking Authority Revenue            Puerto Rico Industrial, Tourist, Educational, Medical             
 Bonds, 4.50%, 8/01/37 (b)    1,355    1,168,769     and Environmental Control Facilities Revenue             
New Jersey State Transportation Trust Fund Authority,             Bonds, (Hospital de la Concepcion), Series A,             
 Transportation System Revenue Bonds:             6.125%, 11/15/30        4,220    4,003,555 
     Series A, 5.625%, 12/15/28 (e)    780    810,186    Housing — 0.8%             
     Series A, 5%, 12/15/32 (a)    730    681,762    Puerto Rico Housing Financing Authority, Capital             
     Series C, 5.049%, 12/15/32 (d)(h)    4,750    1,162,325     Funding Program, Subordinate Revenue Refunding         
     Series C, 4.836%, 12/15/35 (a)(h)    2,760    468,620     Bonds, 5.125%, 12/01/27        1,000    981,570 
     Series D, 5%, 6/15/19 (d)    3,240    3,490,452                 
New Jersey State Transportation Trust Fund Authority,            IDA/PCR/Resource Recovery — 2.1%             
 Transportation System Revenue Refunding Bonds:            Puerto Rico Industrial, Tourist, Educational, Medical             
     Series A, 5.25%, 12/15/20 (d)    4,250    4,836,543     and Environmental Control Facilities Revenue Bonds,         
     Series B, 5.50%, 12/15/21 (b)    3,600    3,957,588     (University Plaza Project), Series A, 5%, 7/01/33 (b)    3,000    2,421,510 

  See Notes to Financial Statements.

SEMI-ANNUAL REPORT

JANUARY 31, 2009

23


Schedule of Investments (continued)       BlackRock MuniYield New Jersey Insured Fund, Inc. (MJI)
(Percentages shown are based on Net Assets)

        Par     
Municipal Bonds        (000)    Value 
     Puerto Rico (concluded)             
Lease Obligations — 0.7%             
Puerto Rico Public Buildings Authority, Government             
 Facilities Revenue Refunding Bonds, Series M-3,             
 6%, 7/01/27 (b)(k)    $ 850    $ 801,210 
Transportation — 1.0%             
Puerto Rico Commonwealth Highway and Transportation         
 Authority, Highway Revenue Refunding Bonds,             
 Series CC, 5.50%, 7/01/31 (e)        1,185    1,195,618 
Utilities — Electric & Gas — 0.7%             
Puerto Rico Electric Power Authority, Power Revenue             
 Bonds, Series RR, 5%, 7/01/28 (l)        1,000    817,710 
Utilities — Water & Sewer — 2.1%             
Puerto Rico Commonwealth Aqueduct and Sewer             
 Authority, Senior Lien Revenue Bonds, Series A,             
 5.125%, 7/01/47 (e)        2,000    1,657,340 
Puerto Rico Commonwealth Infrastructure Financing             
 Authority, Special Tax and Capital Appreciation             
 Revenue Bonds, Series A (h):             
     5.474%, 7/01/30 (g)        2,750    551,238 
     5.04%, 7/01/37 (a)        2,250    262,463 
            2,471,041 
Total Municipal Bonds in Puerto Rico            12,692,214 
Total Municipal Bonds — 147.2%            173,101,635 
Municipal Bonds Transferred to             
Tender Option Bond Trusts (m)             
     New Jersey —8.5%             
Housing — 5.3%             
New Jersey State Housing and Mortgage Finance             
 Agency, Capital Fund Program Revenue Bonds,             
 Series A (d):             
     4.70%, 11/01/25        4,425    4,240,672 
     5%, 5/01/27        1,980    2,005,067 
            6,245,739 
State — 3.2%             
Garden State Preservation Trust of New Jersey, Open             
 Space and Farmland Preservation Revenue Bonds,             
 Series A, 5.75%, 11/01/28 (d)        3,300    3,737,877 
Total Municipal Bonds Transferred to Tender Option             
Bond Trusts — 8.5%            9,983,616 
Total Long-Term Investments             
(Cost — $190,428,078) — 155.7%            183,085,251 

        Par     
Short-Term Securities    (000)    Value 
    New Jersey — 1.9%         
New Jersey State Turnpike Authority, Turnpike Revenue         
 Bonds, VRDN, Series C-2, 2.75%, 2/04/09 (d)(n)    $ 2,200    $ 2,200,000 
        Shares     
    Money Market Funds — 2.1%         
CMA New Jersey Municipal Money Fund,         
 0.22% (o)(p)    2,524,090    2,524,090 
Total Short-Term Securities         
(Cost — $4,724,090) — 4.0%        4,724,090 
Total Investments (Cost — $195,152,168*) — 159.7%    187,809,341 
Other Assets Less Liabilities — 1.0%        1,211,191 
Liability for Trust Certificates, Including Interest         
   Expense and Fees Payable — (4.8)%        (5,694,689) 
Preferred Shares, at Redemption Value — (55.9)%        (65,708,537) 
Net Assets Applicable to Common Shares — 100.0%        $117,617,306 
 
   * The cost and unrealized appreciation (depreciation) of investments as of 
    January 31, 2009, as computed for federal income tax purposes, were 
    as follows:         
    Aggregate cost        $189,449,858 
    Gross unrealized appreciation        $ 6,158,581 
    Gross unrealized depreciation        (13,453,098) 
    Net unrealized depreciation        $ (7,294,517) 
           
(a)    AMBAC Insured.         
(b)    MBIA Insured.         
(c)    US government securities, held in escrow, are used to pay interest on this 
    security as well as to retire the bond in full at the date indicated, typically at 
    a premium to par.         
(d)    FSA Insured.         
(e)    Assured Guaranty Insured.         
(f)    XL Capital Insured.         
(g)    FGIC Insured.         
(h)    Represents a zero-coupon bond. Rate shown reflects the current yield as of 
    report date.         
(i)    Represents a step-up bond that pays an initial coupon rate for the first period 
    and then a higher coupon rate for the following periods. Rate shown is as of 
    report date.         
(j)    Radian Insured.         
(k)    Commonwealth Guaranteed.         
(l)    CIFG Insured.         
(m)     Securities represent underlying bonds transferred to a tender option bond trust 
    in exchange for which the Fund acquired residual interest certificates. These 
    securities serve as collateral in a financing transaction. See Note 1 of the Notes 
    to Financial Statements for details of municipal bonds transferred to tender 
    option bond trusts.         

  See Notes to Financial Statements.

24 SEMI-ANNUAL REPORT JANUARY 31, 2009


Schedule of Investments (concluded) BlackRock MuniYield New Jersey Insured Fund, Inc. (MJI)

(n) Security may have a maturity of more than one year at the time of issuance, but
has variable rate and demand features that qualify it as a short-term security. The
rate disclosed is as of report date. This rate changes periodically based upon
prevailing market rates.
(o) Represents the current yield as of report date.
(p) Investments in companies considered to be an affiliate of the Fund, for purposes
of Section 2(a)(3) of the Investment Company Act of 1940, were as follows:

    Net     
Affiliate    Activity    Income 
CMA New Jersey Municipal Money Fund    1,725,389    $26,135 

For Fund compliance purposes, the Fund’s industry classifications refer to any
one or more of the industry sub-classifications used by one or more widely
recognized market indexes or ratings group indexes, and/or as defined by Fund
management. This definition may not apply for purposes of this report which
may combine industry sub-classifications for reporting ease.
Effective August 1, 2008, the Fund adopted Financial Accounting Standards Board
Statement of Financial Accounting Standards No. 157, “Fair Value Measurements”
(“FAS 157”). FAS 157 clarifies the definition of fair value, establishes a framework
for measuring fair values and requires additional disclosures about the use of fair
value measurements. Various inputs are used in determining the fair value of
investments, which are as follows:
Level 1 — price quotations in active markets/exchanges for identical
securities
Level 2 — other observable inputs (including, but not limited to: quoted prices
for similar assets or liabilities in markets that are not active, inputs other than
quoted prices that are observable for the assets or liabilities (such as interest
rates, yield curves, volatilities, prepayment speeds, loss severities, credit risks
and default rates) or other market-corroborated inputs)
Level 3 — unobservable inputs based on the best information available in the
circumstance, to the extent observable inputs are not available (including the
Fund’s own assumption used in determining the fair value of investments)
The inputs or methodology used for valuing securities are not necessarily an in-
dication of the risk associated with investing in those securities. For information
about the Fund’s policy regarding valuation of investments and other significant
accounting policies, please refer to Note 1 of the Notes to Financial Statements.
The following table summarizes the inputs used as of January 31, 2009 in deter-
mining the fair valuation of the Fund’s investments:

Valuation    Investments in 
Inputs    Securities 
    Assets 
Level 1    $ 2,524,090 
Level 2    185,285,251 
Level 3     
Total    $ 187,809,341 

See Notes to Financial Statements.

SEMI-ANNUAL REPORT

JANUARY 31, 2009

25


Schedule of Investments January 31, 2009 (Unaudited)    BlackRock MuniYield Pennsylvania Insured Fund (MPA) 
                    (Percentages shown are based on Net Assets) 
        Par                    Par     
Municipal Bonds        (000)    Value    Municipal Bonds        (000)    Value 
     Pennsylvania — 129.7%                    Pennsylvania (continued)             
County/City/Special District/School District — 41.3%            Hospitals/Healthcare — 9.1%             
Chambersburg, Pennsylvania, Area School District, GO,            Allegheny County, Pennsylvania, Hospital Development         
 5.25%, 3/01/26 (a)(b)    $ 2,115    $ 2,127,753     Authority, Health Center Revenue Bonds (University of         
Connellsville, Pennsylvania, Area School District, GO,             Pittsburgh Medical Center Health System), Series B,         
 Series B, 5%, 11/15/37 (c)        1,000    961,580     6%, 7/01/26 (b)    $ 2,000     $ 2,056,680 
East Stroudsburg, Pennsylvania, Area School District,            Lehigh County, Pennsylvania, General Purpose Authority,         
 GO, Series A, 7.75%, 9/01/27 (a)(b)        2,000    2,338,880     Hospital Revenue Bonds (Lehigh Valley Health             
Erie County, Pennsylvania, Convention Center                 Network), Series A, 5%, 7/01/33 (c)        7,995    6,921,591 
 Authority, Convention Center Hotel Revenue Bonds,            Monroe County, Pennsylvania, Hospital Authority             
 5%, 1/15/36 (a)(b)        8,850    7,990,576     Revenue Refunding Bonds (Pocono Medical Center),         
Gettysburg, Pennsylvania, Municipal Authority, College             5.125%, 1/01/37        1,265    837,873 
 Revenue Refunding Bonds, 5%, 8/15/23 (b)        4,000    4,008,160    Philadelphia, Pennsylvania, Hospitals and Higher             
North Allegheny, Pennsylvania, School District, GO,                 Education Facilities Authority, Hospital Revenue             
 Series C, 5.25%, 5/01/27 (c)        2,175    2,216,760     Refunding Bonds (Presbyterian Medical Center),             
Northeastern York School District, Pennsylvania, GO,                 6.65%, 12/01/19 (g)        3,000    3,829,110 
 Series B, 5%, 4/01/32 (a)(b)        1,585    1,481,785    Sayre, Pennsylvania, Health Care Facilities Authority,             
Philadelphia, Pennsylvania, Authority for Industrial                 Revenue Refunding Bonds (Guthrie Healthcare             
 Development, Airport Revenue Refunding Bonds                 System), Series A, 5.875%, 12/01/31        590    522,138 
 (Philadelphia Airport System Project), AMT,                                14,167,392 
 Series A (a)(b):                                 
     5.50%, 7/01/17        4,000    4,036,960    Housing — 5.2%             
     5.50%, 7/01/18        3,655    3,671,740    Pennsylvania HFA, Revenue Bonds, DRIVERS, AMT,             
Philadelphia, Pennsylvania, GO, Refunding, Series A,             Series 1248Z, 9.111%, 10/01/09 (b)(h)        2,500    2,507,550 
 5.25%, 12/15/32 (c)        7,000    6,777,470    Pennsylvania HFA, S/F Mortgage Revenue Refunding         
Philadelphia, Pennsylvania, School District, GO:                 Bonds, AMT, Series 96A, 4.70%, 10/01/37        3,000    2,324,100 
     Series B, 5.625%, 8/01/12 (a)(e)        10,000    11,454,100    Philadelphia, Pennsylvania, Housing Authority             
     Series E, 6%, 9/01/38        4,800    4,897,824     Revenue Bonds (Capital Fund Program), Series A,             
Reading, Pennsylvania, School District, GO,                 5.50%, 12/01/18 (c)        3,000    3,252,120 
 5%, 1/15/29 (c)        6,000    5,977,380                    8,083,770 
Scranton, Pennsylvania, School District, GO, Series A,            IDA/PCR/Resource Recovery — 20.1%             
 5%, 7/15/38 (c)        3,500    3,364,375    Delaware County, Pennsylvania, IDA Revenue Bonds             
Shaler Area School District, Pennsylvania, Capital                 (Pennsylvania Suburban Water Company Project),             
 Appreciation, GO, 4.788%, 9/01/30 (d)(f)        6,145    1,622,219     AMT, Series A, 5.15%, 9/01/32 (i)        5,500    4,435,255 
York, Pennsylvania, City School District, GO, Series A,            Delaware County, Pennsylvania, IDA, Water Facilities             
 5.25%, 6/01/22 (f)        1,040    1,082,609     Revenue Refunding Bonds (Aqua Pennsylvania, Inc.         
            64,010,171     Project), AMT, Series B, 5%, 11/01/36 (a)(b)        4,770    3,651,149 
Education — 23.6%                Montgomery County, Pennsylvania, IDA, Water Facilities         
Chambersburg, Pennsylvania, Area School District, GO,             Revenue Bonds (Aqua Pennsylvania, Inc. Project),             
 5.25%, 3/01/27 (a)(b)        2,500    2,501,250     Series A, 5.25%, 7/01/42        1,800    1,367,460 
Pennsylvania State Higher Educational Facilities                Northumberland County, Pennsylvania, IDA,             
 Authority Revenue Bonds (UPMC Health System),                 Water Facilities Revenue Refunding Bonds             
 Series A, 6%, 1/15/22        3,000    3,063,300     (Aqua Pennsylvania Inc. Project), AMT,             
Pennsylvania State Higher Educational Facilities                 5.05%, 10/01/39 (a)(b)        6,000    4,568,880 
 Authority, State System Revenue Bonds, Series AE,            Pennsylvania Economic Development Financing             
 4.75%, 6/15/32 (b)        8,845    8,309,612     Authority, Solid Waste Disposal Revenue Bonds             
Pennsylvania State Public School Building Authority,                 (Waste Management Inc. Project), AMT, Series A,             
 Revenue Refunding Bonds (The School District of                 5.10%, 10/01/27        1,200    842,088 
 Philadelphia Project), Series B, 5%, 6/01/26 (c)        19,025    19,203,074    Pennsylvania State, IDA, EDR, Refunding,             
Pennsylvania State Public School Building Authority,                 5.50%, 7/01/20 (i)        7,000    7,389,900 
 School and Capital Appreciation Revenue Bonds                Philadelphia, Pennsylvania, Authority for Industrial             
 (Corry Area School District) (c)(d):                 Development, Lease Revenue Bonds, Series B,             
     4.848%, 12/15/22        1,980    989,941     5.50%, 10/01/11(c)(e)        3,000    3,363,510 
     4.868%, 12/15/23        1,980    909,493    Philadelphia, Pennsylvania, Qualified Redevelopment         
     4.888%, 12/15/24        1,980    845,579     Authority Revenue Bonds, AMT, Series B,             
     4.918%, 12/15/25        1,980    786,713     5%, 4/15/27 (a)(b)        4,645    3,758,037 
                Philadelphia, Pennsylvania, Redevelopment Authority         
            36,608,962     Revenue Bonds (Neighborhood Transformation),             
                 Series A, 5.50%, 4/15/22 (a)(b)        1,750    1,763,493 
                                31,139,772 

See Notes to Financial Statements.

26 SEMI-ANNUAL REPORT

JANUARY 31, 2009


Schedule of Investments (continued) BlackRock MuniYield Pennsylvania Insured Fund (MPA)
(Percentages shown are based on Net Assets)

    Par     
Municipal Bonds    (000)    Value 
     Pennsylvania (concluded)         
Transportation — 19.6%         
Pennsylvania State Turnpike Commission, Oil Franchise         
 Tax Revenue Bonds, Series C, 5%, 12/01/32 (b)    $ 13,600    $ 13,284,344 
Pennsylvania State Turnpike Commission, Turnpike         
 Revenue Bonds:         
     Series A, 5.50%, 12/01/31 (i)    7,800    7,915,908 
     Sub-Series A, 5%, 6/01/39 (j)    3,500    3,372,810 
Philadelphia, Pennsylvania, Airport Revenue Bonds,         
 AMT, Series A, 5%, 6/15/37 (c)    7,500    5,913,450 
        30,486,512 
Utilities — Electric & Gas — 3.8%         
Philadelphia, Pennsylvania, Gas Works Revenue         
 Bonds, 1998 General Ordinance, 4th Series,         
 5%, 8/01/32 (c)    6,500    5,899,205 
Utilities — Water & Sewer — 5.2%         
Allegheny County, Pennsylvania, Sanitation Authority,         
 Sewer Revenue Refunding Bonds, Series A,         
 5%, 12/01/30 (b)    5,000    4,496,400 
Northampton Borough, Pennsylvania, Municipal         
 Authority, Water Revenue Bonds, 5%, 5/15/34 (b)    935    897,357 
Reading, Pennsylvania, Area Water Authority, Water         
 Revenue Bonds, 5%, 12/01/27 (c)    2,680    2,688,871 
        8,082,628 
Total Municipal Bonds in Pennsylvania — 127.9%        198,478,412 
     Guam — 1.4%         
Transportation — 1.4%         
A.B. Won Guam International Airport Authority,         
 General Revenue Refunding Bonds, AMT, Series C,         
 5%, 10/01/23 (b)    2,500    2,146,475 
Total Municipal Bonds — 129.3%        200,624,887 
Municipal Bonds Transferred to         
Tender Option Bond Trusts (k)         
     Pennsylvania — 15.8%         
County/City/Special District/School District — 4.6%         
East Stroudsburg, Pennsylvania, Area School District,         
 GO, Refunding, 5%, 09/01/25 (c)    7,000    7,163,100 
Education — 11.2%         
Pennsylvania State Public School Building Authority,         
 School Lease Revenue Bonds (The School District of         
 Philadelphia Project), 5.25%, 06/01/13 (c)(e)    15,000    17,345,700 
Total Municipal Bonds Transferred to         
Tender Option Bond Trusts — 15.8%        24,508,800 
Total Long-Term Investments         
(Cost — $235,704,212) — 145.1%        225,133,687 

    Par     
Short-Term Securities    (000)    Value 
     Pennsylvania — 9.7%         
Philadelphia, Pennsylvania, GO, Refunding, VRDN,         
 Series B, 3.75%, 02/05/09 (c)(n)    $ 15,000    $ 15,000,000 
    Shares     
    Money Market Funds — 0.9%         
CMA Pennsylvania Municipal Money Fund,         
 0.15% (l)(m)    1,455,478    1,455,478 
Total Short-Term Securities         
(Cost — $16,455,478) — 10.6%        16,455,478 
Total Investments (Cost — $252,159,690*) — 155.7%    241,589,165 
Other Assets Less Liabilities — 1.3%        1,996,547 
Liability for Trust Certificates, Including Interest         
   Expense and Fees Payable — (7.1)%        (11,058,716) 
Preferred Shares, at Redemption Value — (49.9)%        (77,408,443) 
Net Assets Applicable to Common Shares — 100.0%        $155,118,553 

* The cost and unrealized appreciation (depreciation) of investments as of
January 31, 2009, as computed for federal income tax purposes, were
as follows:

    Aggregate cost        $241,260,957 
    Gross unrealized appreciation        $ 8,675,110 
    Gross unrealized depreciation        (19,346,902) 
    Net unrealized depreciation        $ (10,671,792) 
(a)    FGIC Insured.         
(b)    MBIA Insured.         
(c)    FSA Insured.         
(d)    Represents a zero-coupon bond. Rate shown reflects the current yield as of 
    report date.         
(e)    US government securities, held in escrow, are used to pay interest on this 
    security as well as to retire the bond in full at the date indicated, typically at 
    a premium to par.         
(f)    XL Capital Insured.         
(g)    Security is collateralized by Municipal or US Treasury Obligations.     
(h)    Variable rate security. Rate shown is as of report date.     
(i)    AMBAC Insured.         
(j)    Assured Guaranty Insured.         
(k)    Securities represent underlying bonds transferred to a tender option bond trust 
    in exchange for which the Fund acquired residual interest certificates. These 
    securities serve as collateral in a financing transaction. See Note 1 of the Notes 
    to Financial Statements for details of municipal bonds transferred to tender 
    option bond trusts.         
(l)    Investments in companies considered to be an affiliate of the Fund, for purposes 
    of Section 2(a)(3) of the Investment Company Act of 1940, were as follows: 
   
        Net     
    Affiliate    Activity    Income 
    CMA Pennsylvania Municipal Money Fund    (10,605,684)    $93,711 
   
 
 
(m)      Represents the current yield as of report date.     
(n)    Security may have a maturity of more than one year at the time of issuance, but 
    has variable rate and demand features that qualify it as a short-term security. The 
    rate disclosed is as of report date. This rate changes periodically based upon 
    prevailing market rates.         

See Notes to Financial Statements.

SEMI-ANNUAL REPORT

JANUARY 31, 2009

27


Schedule of Investments (concluded) BlackRock MuniYield Pennsylvania Insured Fund (MPA)

For Fund compliance purposes, the Fund’s industry classifications refer to any
one or more of the industry sub-classifications used by one or more widely
recognized market indexes or ratings group indexes, and/or as defined by Fund
management. This definition may not apply for purposes of this report which
may combine industry sub-classifications for reporting ease.
Effective August 1, 2008, the Fund adopted Financial Accounting Standards Board
Statement of Financial Accounting Standards No. 157, “Fair Value Measurements”
(“FAS 157”). FAS 157 clarifies the definition of fair value, establishes a framework
for measuring fair values and requires additional disclosures about the use of fair
value measurements. Various inputs are used in determining the fair value of
investments, which are as follows:
Level 1 — price quotations in active markets/exchanges for identical
securities
Level 2 — other observable inputs (including, but not limited to: quoted prices
for similar assets or liabilities in markets that are not active, inputs other than
quoted prices that are observable for the assets or liabilities (such as interest
rates, yield curves, volatilities, prepayment speeds, loss severities, credit risks
and default rates) or other market-corroborated inputs)
Level 3 — unobservable inputs based on the best information available in the
circumstance, to the extent observable inputs are not available (including the
Fund’s own assumption used in determining the fair value of investments)
The inputs or methodology used for valuing securities are not necessarily an in-
dication of the risk associated with investing in those securities. For information
about the Fund’s policy regarding valuation of investments and other significant
accounting policies, please refer to Note 1 of the Notes to Financial Statements.
The following table summarizes the inputs used as of January 31, 2009 in deter-
mining the fair valuation of the Fund’s investments:

Valuation    Investments in 
Inputs    Securities 
    Assets 
Level 1    $ 1,455,478 
Level 2    240,133,687 
Level 3     
Total    $ 241,589,165 

See Notes to Financial Statements.

28 SEMI-ANNUAL REPORT

JANUARY 31, 2009


Statements of Assets and Liabilities                     
 
    BlackRock    BlackRock    BlackRock    BlackRock    BlackRock 
    MuniHoldings    MuniYield    MuniYield    MuniYield    MuniYield 
    New Jersey    Insured    Michigan    New Jersey    Pennsylvania 
    Insured    Investment    Insured    Insured    Insured 
    Fund, Inc.    Fund    Fund, Inc.    Fund, Inc.    Fund 
January 31, 2009 (Unaudited)    (MUJ)    (MFT)    (MIY)    (MJI)    (MPA) 
     Assets                     
Investments at value — unaffiliated1    $482,080,752    $165,927,249    $385,314,730    $185,285,251    $240,133,687 
Investments at value — affiliated2    310,880    5,548,510    16,825,573    2,524,090    1,455,478 
Cash    74,598    4,289    70,279    63,820    67,511 
Interest receivable    5,306,580    2,530,538    5,087,521    1,721,406    2,653,093 
Investments sold receivable        1,219,034            3,789,938 
Prepaid expenses    18,238    6,803    15,757    7,880    9,842 
Other assets    2,585        2,095    10    235 
Total assets    487,793,633    175,236,423    407,315,955    189,602,457    248,109,784 
 
     Accrued Liabilities                     
Investments purchased payable        1,311,423            3,769,763 
Income dividends payable — Common Shares    1,126,007    452,172    983,140    475,313    608,470 
Investment advisory fees payable    210,424    71,789    170,198    80,569    100,655 
Interest expense and fees payable    103,615    72,595    77,495    39,689    58,716 
Other affiliates payable    2,349    952    2,308    1,092    1,376 
Officer’s and Directors’/Trustees’ fees payable    472    53    409    177    74 
Other accrued expenses payable    88,241    13,531    30,372    24,774    43,734 
Total accrued liabilities    1,531,108    1,922,515    1,263,922    621,614    4,582,788 
 
     Other Liabilities                     
Trust certificates3    14,825,000    8,490,632    16,190,000    5,655,000    11,000,000 
Total Liabilities    16,356,108    10,413,147    17,453,922    6,276,614    15,582,788 
 
     Preferred Shares at Redemption Value                     
Par value4 per share at $25,000 per share liquidation preference,                     
plus unpaid dividends    176,716,565    62,257,607    144,668,870    65,708,537    77,408,443 
Net Assets Applicable to Common Shareholders    $294,720,960    $102,565,669    $245,193,163    $117,617,306    $155,118,553 
 
     Net Assets Applicable to Common Shareholders Consist of                     
Common Shares, par value $0.10 per share5,6    $ 2,124,541    $ 845,181    $ 1,820,630    $ 880,210    $ 1,148,057 
Paid-in capital in excess of par    319,388,284    117,070,606    262,101,745    123,256,564    169,088,427 
Undistributed net investment income    1,507,942    463,036    1,534,634    1,588,549    803,329 
Accumulated net realized loss    (25,698,309)    (6,031,105)    (10,605,858)    (765,190)    (5,350,735) 
Net unrealized appreciation/depreciation    (2,601,498)    (9,782,049)    (9,657,988)    (7,342,827)    (10,570,525) 
Net Assets Applicable to Common Shareholders    $294,720,960    $102,565,669    $245,193,163    $117,617,306    $155,118,553 
Net asset value per Common Share5    $ 13.87    $ 12.14    $ 13.47    $ 13.36    $ 13.51 
     1 Investments at cost — unaffiliated    $484,682,250    $175,709,298    $394,972,718    $192,628,078    $250,704,212 
     2 Investments at cost — affiliated    $ 310,880    $ 5,548,510    $ 16,825,573    $ 2,524,090    $ 1,455,478 
     3 Represents short-term floating rate certificates issued by tender option                     
          bond trusts.                     
     4 Preferred Shares outstanding:                     
          Par value $0.05 per share        2,490    4,909    2,002    3,096 
          Par value $0.10 per share    7,068        877    626     
     5 Common Shares outstanding    21,245,413    8,451,814    18,206,301    8,802,099    11,480,567 
     6 Common Shares authorized    200,000,000    unlimited    200,000,000    200,000,000    unlimited 
 
See Notes to Financial Statements.                     

SEMI-ANNUAL REPORT

JANUARY 31, 2009

29


Statements of Operations             
 
    BlackRock    BlackRock    BlackRock 
    MuniHoldings    MuniYield    MuniYield 
    New Jersey    Insured    Michigan 
    Insured    Investment         Insured 
       Fund, Inc.    Fund    Fund, Inc. 
Six Months Ended January 31, 2009 (Unaudited)                 (MUJ)    (MFT)    (MIY) 
 
     Investment Income             
Interest    $ 12,217,805    $ 4,680,795    $ 10,693,423 
Income — affiliated    59,996    36,359    60,484 
Total income    12,277,801    4,717,154    10,753,907 
 
     Expenses             
Investment advisory    1,355,713    450,246    1,047,268 
Commissions for Preferred Shares    194,132    66,868    182,934 
Accounting services    75,249    27,379    46,143 
Professional    59,824    41,968    50,692 
Transfer agent    34,837    20,150    32,587 
Printing    28,727    10,795    22,033 
Officer and Directors/Trustees    21,267    7,328    14,293 
Custodian    14,891    6,607    11,671 
Registration    5,036    5,608    4,413 
Miscellaneous    48,299    29,282    40,572 
Total expenses excluding interest expense and fees    1,837,975    666,231    1,452,606 
Interest expense and fees1    329,159    158,745    352,545 
Total expenses    2,167,134    824,976    1,805,151 
Less fees waived by advisor    (182,768)    (17,308)    (22,858) 
Total expenses after waiver    1,984,366    807,668    1,782,293 
Net investment income    10,293,435    3,909,486    8,971,614 
 
     Realized and Unrealized Loss             
Net realized loss from investments    (320,693)    (2,962,409)    (747,109) 
Net change in unrealized appreciation/depreciation on investments    (10,665,736)    (8,010,824)    (12,574,838) 
Total realized and unrealized loss    (10,986,429)    (10,973,233)    (13,321,947) 
 
     Dividends to Preferred Shareholders From             
Net investment income    (2,776,849)    (1,036,701)    (2,363,868) 
Net Decrease in Net Assets Applicable to Common Shareholders Resulting from Operations    $ (3,469,843)    $ (8,100,448)    $ (6,714,201) 
 
   1 Related to tender option bond trusts.             

See Notes to Financial Statements.

30 SEMI-ANNUAL REPORT

JANUARY 31, 2009


Statements of Operations (concluded)         
 
    BlackRock    BlackRock 
    MuniYield    MuniYield 
    New Jersey    Pennsylvania 
     Insured        Insured 
    Fund, Inc.          Fund 
January 31, 2009 (Unaudited)                     (MJI)         (MPA) 
 
     Investment Income         
Interest    $ 5,008,711    $ 6,210,486 
Income — affiliated    26,135    93,711 
Total income    5,034,846    6,304,197 
 
     Expenses         
Investment advisory    479,151    638,685 
Commissions for Preferred Shares    65,653    83,856 
Professional    45,713    40,372 
Accounting services    28,360    37,259 
Transfer agent    18,215    27,332 
Printing    12,218    15,051 
Officer and Directors/Trustees    7,790    10,873 
Custodian    6,494    8,317 
Registration    4,737    5,040 
Miscellaneous    27,077    30,449 
Total expenses excluding interest expense and fees    695,408    897,234 
Interest expense and fees1    116,975    285,845 
Total expenses    812,383    1,183,079 
Less fees waived by advisor    (6,899)    (30,430) 
Less fees paid indirectly        (11) 
Total expenses after waiver and fees paid indirectly    805,484    1,152,638 
Net investment income    4,229,362    5,151,559 
 
     Realized and Unrealized Gain (Loss)         
Net realized loss from:         
     Investments    (19,295)    (3,070,518) 
     Forward interest rate swaps        (931,500) 
    (19,295)    (4,002,018) 
Net change in unrealized appreciation/depreciation on:         
     Investments    (7,686,665)    (5,469,314) 
     Forward interest rate swaps        227,038 
    (7,686,665)    (5,242,276) 
Total realized and unrealized loss    (7,705,960)    (9,244,294) 
 
     Dividends and Distributions to Preferred Shareholders From         
 
Net investment income    (1,041,936)    (1,257,064) 
Net realized gain    (95,183)     
Total dividends and distributions to Preferred Shareholders    (1,137,119)    (1,257,064) 
Net Decrease in Net Assets Applicable to Common Shareholders Resulting from Operations    $ (4,613,717)    $ (5,349,799) 
 
   1 Related to tender option bond trusts.         

See Notes to Financial Statements.

SEMI-ANNUAL REPORT

JANUARY 31, 2009

31


Statements of Changes in Net Assets    BlackRock MuniHoldings New Jersey Insured Fund, Inc. (MUJ) 
 
               Six Months     
        Ended     
        January 31,         Year Ended 
        2009             July 31, 
Increase (Decrease) in Net Assets Applicable to Common Shareholders:        (Unaudited)    2008 
     Operations             
Net investment income        $ 10,293,435    $ 19,736,589 
Net realized loss        (320,693)    (1,469,777) 
Net change in unrealized appreciation/depreciation        (10,665,736)    (8,375,097) 
Dividends to Preferred Shareholders from net investment income        (2,776,849)    (6,691,973) 
Net increase (decrease) in net assets applicable to Common Shareholders resulting from operations        (3,469,843)    3,199,742 
 
     Dividends to Common Shareholders From             
Net investment income        (6,756,041)    (14,021,973) 
 
     Net Assets Applicable to Common Shareholders             
Total decrease in net assets applicable to Common Shareholders        (10,225,884)    (10,822,231) 
Beginning of period        304,946,844    315,769,075 
End of period        $ 294,720,960    $ 304,946,844 
End of period undistributed net investment income        $ 1,507,942    $ 747,397 
 
 
    BlackRock MuniYield Insured Investment Fund (MFT) 
 
    Six Months         
    Ended    Period     
    January 31,    November 1 2007    Year Ended 
    2009    to July 31,    October 31, 
Increase (Decrease) in Net Assets Applicable to Common Shareholders:    (Unaudited)    2008             2007 
     Operations             
Net investment income    $ 3,909,486    $ 5,967,801    $ 8,056,928 
Net realized gain (loss)    (2,962,409)    (372,939)    176,914 
Net change in unrealized appreciation/depreciation    (8,010,824)    (7,756,323)    (4,348,589) 
Dividends to Preferred Shareholders from net investment income    (1,036,701)    (1,872,136)    (2,631,621) 
Net increase (decrease) in net assets applicable to Common Shareholders resulting from operations    (8,100,448)    (4,033,597)    1,253,632 
 
     Dividends to Common Shareholders From             
Net investment income    (2,783,140)    (4,090,678)    (5,721,878) 
 
     Net Assets Applicable to Common Shareholders             
Total decrease in net assets applicable to Common Shareholders    (10,883,588)    (8,124,275)    (4,468,246) 
Beginning of period    113,449,257    121,573,532    126,041,778 
End of period    $ 102,565,669    $ 113,449,257    $ 121,573,532 
End of period undistributed net investment income    $ 463,036    $ 373,391    $ 339,357 

See Notes to Financial Statements.

32 SEMI-ANNUAL REPORT

JANUARY 31, 2009


Statements of Changes in Net Assets    BlackRock MuniYield Michigan Insured Fund, Inc. (MIY) 
 
    Six Months         
    Ended    Period     
    January 31,    November 1 2007    Year Ended 
    2009    to July 31,    October 31, 
Increase (Decrease) in Net Assets Applicable to Common Shareholders:    (Unaudited)    2008             2007 
     Operations             
Net investment income    $ 8,971,614    $ 12,731,272    $ 19,208,577 
Net realized gain (loss)    (747,109)    (1,246,561)    1,570,157 
Net change in unrealized appreciation/depreciation    (12,574,838)    (13,574,409)    (9,721,365) 
Dividends to Preferred Shareholders from net investment income    (2,363,868)    (4,212,108)    (5,850,606) 
Net increase (decrease) in net assets applicable to Common Shareholders resulting from operations    (6,714,201)    (6,301,806)    5,206,763 
 
     Dividends to Common Shareholders From             
Net investment income    (5,898,841)    (9,485,483)    (12,962,886) 
 
     Net Assets Applicable to Common Shareholders             
Total decrease in net assets applicable to Common Shareholders    (12,613,042)    (15,787,289)    (7,756,123) 
Beginning of period    257,806,205    273,593,494    281,349,617 
End of period    $ 245,193,163    $ 257,806,205    $ 273,593,494 
End of period undistributed net investment income    $ 1,534,634    $ 825,729    $ 1,796,256 
 
    BlackRock MuniYield New Jersey Insured Fund, Inc. (MJI) 
 
    Six Months         
    Ended    Period     
    January 31,    November 1 2007    Year Ended 
    2009    to July 31,    October 31, 
Increase (Decrease) in Net Assets Applicable to Common Shareholders:    (Unaudited)    2008             2007 
     Operations             
Net investment income    $ 4,229,362    $ 6,056,221    $ 8,403,981 
Net realized gain (loss)    (19,295)    (17,732)    588,462 
Net change in unrealized appreciation/depreciation    (7,686,665)    (6,708,329)    (4,321,927) 
Dividends and distributions to Preferred Shareholders from:             
     Net investment income    (1,041,936)    (1,835,167)    (2,420,847) 
     Net realized gain    (95,183)    (42,392)    (23,780) 
Net increase (decrease) in net assets applicable to Common Shareholders resulting from operations    (4,613,717)    (2,547,399)    2,225,889 
 
     Dividends and Distributions to Common Shareholders From             
Net investment income    (2,851,881)    (4,289,500)    (5,747,771) 
Net realized gain    (150,243)    (103,918)    (70,742) 
Net decrease in net assets resulting from dividends and distributions to Common Shareholders    (3,002,124)    (4,393,418)    (5,818,513) 
 
     Net Assets Applicable to Common Shareholders             
Total decrease in net assets applicable to Common Shareholders    (7,615,841)    (6,940,817)    (3,592,624) 
Beginning of period    125,233,147    132,173,964    135,766,588 
End of period    $ 117,617,306    $ 125,233,147    $ 132,173,964 
End of period undistributed net investment income    $ 1,588,549    $ 1,253,004    $ 1,307,514 
 
See Notes to Financial Statements.             

SEMI-ANNUAL REPORT

JANUARY 31, 2009

33


Statements of Changes in Net Assets    BlackRock MuniYield Pennsylvania Insured Fund (MPA) 
 
    Six Months         
    Ended    Period     
    January 31,    November 1 2007    Year Ended 
    2009    to July 31,    October 31, 
Increase (Decrease) in Net Assets Applicable to Common Shareholders:    (Unaudited)    2008             2007 
     Operations             
Net investment income    $ 5,151,559    $ 8,207,974    $ 11,615,514 
Net realized gain (loss)    (4,002,018)    (312,302)    2,337,245 
Net change in unrealized appreciation/depreciation    (5,242,276)    (13,306,589)    (6,999,004) 
Dividends to Preferred Shareholders from net investment income    (1,257,064)    (2,559,463)    (3,638,710) 
Net increase (decrease) in net assets applicable to Common Shareholders resulting from operations    (5,349,799)    (7,970,380)    3,315,045 
 
     Dividends to Common Shareholders From             
Net investment income    (3,650,820)    (5,717,322)    (7,910,111) 
 
     Net Assets Applicable to Common Shareholders             
Total decrease in net assets applicable to Common Shareholders    (9,000,619)    (13,687,702)    (4,595,066) 
Beginning of period    164,119,172    177,806,874    182,401,940 
End of period    $ 155,118,553    $ 164,119,172    $ 177,806,874 
End of period undistributed net investment income    $ 803,329    $ 559,654    $ 677,381 

See Notes to Financial Statements.

34 SEMI-ANNUAL REPORT

JANUARY 31, 2009


Financial Highlights        BlackRock MuniHoldings New Jersey Insured Fund, Inc. (MUJ) 
 
    Six Months                         
    Ended                         
    January 31,                         
    2009            Year Ended July 31,         
    (Unaudited)    2008    2007    2006        2005    2004 
     Per Share Operating Performance                             
Net asset value, beginning of period    $ 14.35    $ 14.86    $ 14.91    $ 15.62    $ 15.03    $ 14.46 
Net Investment income1    0.48    0.93    1.03    1.03        1.04    1.07 
Net realized and unrealized gain (loss)    (0.51)    (0.47)    (0.03)    (0.61)        0.66    0.51 
Dividends to Preferred Shareholders from net investment income    (0.13)    (0.31)    (0.31)    (0.26)        (0.16)    (0.08) 
Net increase (decrease) from investment operations    (0.16)    0.15    0.69    0.16        1.54    1.50 
Dividends to Common Shareholders from net investment income    (0.32)    (0.66)    (0.74)    (0.87)        (0.95)    (0.93) 
Net asset value, end of period    $ 13.87    $ 14.35    $ 14.86    $ 14.91    $ 15.62    $ 15.03 
Market price, end of period    $ 11.63    $ 12.93    $ 14.40    $ 14.98    $ 15.89    $ 14.17 
 
     Total Investment Return2                             
Based on net asset value    (0.56)%3    1.35%    4.71%    1.09%        10.63%    10.90% 
Based on market price    (7.46)%3    (5.76)%    0.99%    (0.16)%        19.37%    11.24% 
 
     Ratios to Average Net Assets Applicable to Common Shares                             
Total expenses after waiver and excluding interest expense and fees 4,5    1.14%6    1.15%    1.17%    1.15%        1.14%    1.13% 
Total expenses after waiver5    1.37%6    1.23%    1.40%    1.39%        1.25%    1.19% 
Total expenses5    1.49%6    1.30%    1.45%    1.45%        1.31%    1.27% 
Net investment income5    7.08%6    6.22%    6.77%    6.80%        6.69%    6.97% 
Dividends paid to Preferred Shareholders    1.91%6    2.11%    2.03%    1.72%        1.02%    0.54% 
Net investment income to Common Shareholders    5.17%6    4.11%    4.74%    5.08%        5.67%    6.43% 
 
     Supplemental Data                             
Net assets applicable to Common Shares, end of period (000)    $ 294,721    $ 304,947    $ 315,769    $ 315,649    $ 328,853    $ 316,171 
Preferred Shares outstanding at liquidation preference,                             
end of period (000)    $ 176,700    $ 176,700    $ 203,000    $ 203,000    $ 203,000    $ 203,000 
Portfolio turnover    5%    12%    17%    16%        29%    8% 
Asset coverage per Preferred Share, end of period    $ 66,700    $ 68,1527    $ 63,8987    $ 63,8847    $ 65,5027    $ 63,9397 

1 Based on average shares outstanding.
2 Total investment returns based on market value, which can be significantly greater or lesser than the net asset value, may result in substantially different returns.
Total investment returns exclude the effects of sales charges.
3 Aggregate total investment return.
4 Interest expense and fees relate to tender option bond trusts. See Note 1 of the Notes to Financial Statements for details of municipal bonds transferred to tender option
bond trusts.
5 Do not reflect the effect of dividends to Preferred Shareholders.
6 Annualized.
7 Amounts have been recalculated to conform with current year presentation.

See Notes to Financial Statements.

SEMI-ANNUAL REPORT

JANUARY 31, 2009

35


Financial Highlights                BlackRock MuniYield Insured Investment Fund (MFT) 
 
    Six Months                             
    Ended    Period                         
    January 31,    November 1,                         
    2009    2007 to July 31,        Year Ended October 31,         
    (Unaudited)    2008    2007    2006    2005        2004    2003 
     Per Share Operating Performance                                 
Net asset value, beginning of period    $ 13.42    $ 14.38    $ 14.91    $ 14.72    $ 15.22    $ 15.04    $ 15.04 
Net investment income1    0.46    0.71    0.95    0.97    0.98        0.98    1.05 
Net realized and unrealized gain (loss)    (1.29)    (0.97)    (0.49)    0.24    (0.38)        0.20    (0.06) 
Dividends to Preferred Shareholders from                                 
   net investment income    (0.12)    (0.22)    (0.31)    (0.27)    (0.17)        (0.07)    (0.07) 
Net increase (decrease) from investment operations    (0.95)    (0.48)    0.15    0.94    0.43        1.11    0.92 
Dividends to Common Shareholders from                                 
   net investment income    (0.33)    (0.48)    (0.68)    (0.75)    (0.90)        (0.93)    (0.92) 
Capital charges with respect to the issuance of                                 
   Preferred Shares                    (0.03)             
Net asset value, end of period    $ 12.14    $ 13.42    $ 14.38    $ 14.91    $ 14.72    $ 15.22    $ 15.04 
Market price, end of period    $ 10.51    $ 11.75    $ 12.74    $ 14.21    $ 14.18    $ 14.98    $ 14.18 
 
     Total Investment Return2                                 
Based on net asset value    (6.49)%3    (2.97)%3    1.39%    6.87%    2.72%        7.98%    6.45% 
Based on market price    (7.54)%3    (4.11)%3    (5.75)%    5.73%    0.54%        12.73%    5.56% 
 
     Ratios to Average Net Assets Applicable to Common Shares                             
Total expenses after waiver and excluding interest                                 
   expense and fees4,5    1.25%6    1.18%6    1.20%    1.17%    1.20%        1.09%    1.08% 
Total expenses after waiver5    1.56%6    1.49%6    1.52%    1.45%    1.38%        1.27%    1.25% 
Total expenses5    1.59%6    1.51%6    1.54%    1.46%    1.38%        1.28%    1.25% 
Net investment income5    7.53%6    6.60%6    6.53%    6.58%    6.50%        6.54%    6.86% 
Dividends paid to Preferred Shareholders    2.00%6    2.07%6    2.13%    1.87%    1.13%        0.48%    0.47% 
Net investment income to Common Shareholders    5.53%6    4.53%6    4.40%    4.71%    5.37%        6.06%    6.39% 
 
     Supplemental Data                                 
Net assets applicable to Common Shares,                                 
   end of period (000)    $ 102,566    $ 113,449    $ 121,574    $ 126,042    $ 124,422    $ 128,455    $ 126,915 
Preferred Shares outstanding at liquidation                                 
   preference, end of period (000)    $ 62,250    $ 62,250    $ 72,000    $ 72,000    $ 72,000    $ 60,000    $ 60,000 
Portfolio turnover    15%    21%    26%    34%    52%        28%    40% 
Asset coverage per Preferred Share, end of period    $ 66,194    $ 70,5697    $ 67,2207    $ 68,7697    $ 68,2127    $ 78,5287    $ 77,8857 

1 Based on average shares outstanding.
2 Total investment returns based on market value, which can be significantly greater
or lesser than the net asset value, may result in substantially different returns.
Total investment returns exclude the effects of sales charges.
3 Aggregate total investment return.
4 Interest expense and fees relate to tender option bond trusts. See Note 1 of
the Notes to Financial Statements for details of municipal bonds transferred to
tender option bond trusts.
5 Do not reflect the effect of dividends to Preferred Shareholders.
6 Annualized.
7 Amounts have been recalculated to conform with current
year presentation.

See Notes to Financial Statements.

36 SEMI-ANNUAL REPORT

JANUARY 31, 2009


Financial Highlights                BlackRock MuniYield Michigan Insured Fund, Inc. (MIY) 
 
    Six Months                             
    Ended    Period                         
    January 31,    November 1,                         
    2009    2007 to July 31,        Year Ended October 31,         
    (Unaudited)    2008    2007    2006    2005        2004    2003 
     Per Share Operating Performance                                 
Net asset value, beginning of period    $ 14.16    $ 15.03    $ 15.45    $ 15.32    $ 15.96    $ 15.94    $ 15.74 
Net investment income1    0.49    0.70    1.06    1.04    1.08        1.06    1.10 
Net realized and unrealized gain (loss)    (0.73)    (0.82)    (0.45)    0.22    (0.54)        0.03    0.15 
Dividends to Preferred Shareholders from                                 
   net investment income    (0.13)    (0.23)    (0.32)    (0.29)    (0.18)        (0.07)    (0.07) 
Net increase (decrease) from investment operations    (0.37)    (0.35)    (0.29)    0.97    0.36        1.02    1.18 
Dividends to Common Shareholders from                                 
   net investment income    (0.32)    (0.52)    (0.71)    (0.84)    (0.98)        (1.00)    (0.98) 
Capital charges with respect to the issuance                                 
   of Preferred Shares                    (0.02)             
Net asset value, end of period    $ 13.47    $ 14.16    $ 15.03    $ 15.45    $ 15.32    $ 15.96    $ 15.94 
Market price, end of period    $ 10.61    $ 12.30    $ 13.40    $ 14.67    $ 15.31    $ 15.37    $ 14.69 
 
     Total Investment Return2                                 
Based on net asset value    (1.89)%3    (2.02)%3    2.30%    6.64%    2.24%        7.04%    8.26% 
Based on market price    (11.04)%3    (4.54)%3    (3.95)%    1.32%    6.10%        11.85%    12.57% 
 
     Ratios to Average Net Assets Applicable to Common Shares                             
Total expenses after waiver and excluding interest                                 
   expense and fees4,5    1.17%6    1.13%6    1.12%    1.11%    1.10%        1.00%    1.01% 
Total expenses after waiver5    1.45%6    1.40%6    1.55%    1.61%    1.42%        1.19%    1.20% 
Total expenses5    1.47%6    1.42%6    1.55%    1.62%    1.42%        1.22%    1.21% 
Net investment income5    7.32%6    6.19%6    6.95%    6.84%    6.84%        6.69%    6.83% 
Dividends paid to Preferred Shareholders    1.93%6    2.05%6    2.12%    1.87%    1.13%        0.46%    0.45% 
Net investment income to Common Shareholders    5.39%6    4.14%6    4.83%    4.97%    5.71%        6.23%    6.38% 
 
     Supplemental Data                                 
Net assets applicable to Common Shares,                                 
   end of period (000)    $ 245,193    $ 257,806    $ 273,593    $ 281,350    $ 278,250    $ 289,695    $ 289,364 
Preferred Shares outstanding at liquidation                                 
   preference, end of period (000)    $ 144,650    $ 144,650    $ 165,000    $ 165,000    $ 165,000    $ 140,000    $ 140,000 
Portfolio turnover    5%    21%    10%    15%    25%        32%    29% 
Asset coverage per Preferred Share, end of period    $ 67,380    $ 69,5637    $ 66,4617    $ 67,6387    $ 67,1657    $ 76,7347    $ 76,6747 

1 Based on average shares outstanding.
2 Total investment returns based on market value, which can be significantly greater or lesser than the net asset value, may result in substantially different returns.
Total investment returns exclude the effects of sales charges.
3 Aggregate total investment return.
4 Interest expense and fees relate to tender option bond trusts. See Note 1 of the Notes to Financial Statements for details of municipal bonds transferred to
tender option bond trusts.
5 Do not reflect the effect of dividends to Preferred Shareholders.
6 Annualized.
7 Amounts have been recalculated to conform with current year presentation.

See Notes to Financial Statements.

SEMI-ANNUAL REPORT

JANUARY 31, 2009

37


Financial Highlights            BlackRock MuniYield New Jersey Insured Fund, Inc. (MJI) 
 
    Six Months                             
    Ended    Period                         
    January 31,    November 1,                         
    2009    2007 to July 31,        Year Ended October 31,         
    (Unaudited)    2008    2007    2006    2005        2004    2003 
     Per Share Operating Performance                                 
Net asset value, beginning of period    $ 14.23    $ 15.02    $ 15.42    $ 15.07    $ 15.46    $ 15.25    $ 15.14 
Net investment income1    0.48    0.69    0.96    0.97    0.96        1.03    1.06 
Net realized and unrealized gain (loss)    (0.88)    (0.76)    (0.42)    0.36    (0.27)        0.21    0.06 
Dividends and distributions to Preferred                                 
   Shareholders from:                                 
     Net investment income    (0.12)    (0.21)    (0.28)    (0.25)    (0.16)        (0.06)    (0.06) 
     Net realized gain    (0.01)    (0.01)             (0.00)2                             (0.00)2 
Net increase (decrease) from investment operations    (0.53)    (0.29)    0.26    1.08    0.53        1.18    1.06 
Dividends and distributions to Common                                 
   Shareholders from:                                 
     Net investment income    (0.32)    (0.49)    (0.65)    (0.73)    (0.92)        (0.94)    (0.94) 
     Net realized gain    (0.02)    (0.01)    (0.01)                    (0.01) 
Total dividends and distributions to                                 
   Common Shareholders    (0.34)    (0.50)    (0.66)    (0.73)    (0.92)        (0.94)    (0.95) 
Capital charges with respect to the issuance                                 
   of Preferred Shares                    0.003        (0.03)     
Net asset value, end of period    $ 13.36    $ 14.23    $ 15.02    $ 15.42    $ 15.07    $ 15.46    $ 15.25 
Market price, end of period    $ 11.24    $ 12.81    $ 13.70    $ 14.96    $ 14.65    $ 15.16    $ 14.39 
 
     Total Investment Return4                                 
Based on net asset value    (3.14)%5    (1.67)%5    2.00%    7.50%    3.49%        7.99%    7.24% 
Based on market price    (9.48)%5    (2.95)%5    (4.10)%    7.28%    2.60%        12.23%    6.02% 
 
     Ratios to Average Net Assets Applicable to Common Shares                             
Total expenses after waiver and excluding interest                                 
   expense and fees6,7    1.18%8    1.18%8    1.17%    1.15%    1.16%        1.06%    1.03% 
Total expenses after waiver7    1.38%8    1.24%8    1.37%    1.59%    1.52%        1.33%    1.29% 
Total expenses7    1.39%8    1.24%8    1.37%    1.59%    1.52%        1.35%    1.30% 
Net investment income7    7.34%8    6.18%8    6.30%    6.46%    6.21%        6.79%    6.89% 
Dividends paid to Preferred Shareholders    1.78%8    1.87%8    1.81%    1.63%    1.03%        0.42%    0.38% 
Net investment income to Common Shareholders    5.56%8    4.31%8    4.49%    4.83%    5.18%        6.37%    6.51% 
 
     Supplemental Data                                 
Net assets applicable to Common Shares,                                 
   end of period (000)    $ 117,617    $ 125,233    $ 132,174    $ 135,767    $ 132,622    $ 135,370    $ 133,240 
Preferred Shares outstanding at liquidation                                 
   preference, end of period (000)    $ 65,700    $ 65,700    $ 73,500    $ 73,500    $ 73,500    $ 73,500    $ 56,000 
Portfolio turnover    4%    13%    23%    11%    29%        16%    21% 
Asset coverage per Preferred Share, end of period    $ 69,759    $ 72,6669    $ 69,9659    $ 71,1859    $ 70,1109    $ 71,0509    $ 84,4869 

1 Based on average shares outstanding.
2 Amount is less than ($0.01) per share.
3 Amount is less than $0.01 per share.
4 Total investment returns based on market value, which can be significantly greater
or lesser than the net asset value, may result in substantially different returns.
Total investment returns exclude the effects of sales charges.
5 Aggregate total investment return.

6 Interest expense and fees relate to tender option bond trusts. See Note 1 of
the Notes to Financial Statements for details of municipal bonds transferred to
tender option bond trusts.
7 Do not reflect the effect of dividends to Preferred Shareholders.
8 Annualized.
9 Amounts have been recalculated to conform with current year presentation.

See Notes to Financial Statements.

38 SEMI-ANNUAL REPORT

JANUARY 31, 2009


Financial Highlights                BlackRock MuniYield Pennsylvania Insured Fund (MPA) 
 
    Six Months                             
    Ended    Period                         
    January 31,    November 1,                         
    2009    2007 to July 31,        Year Ended October 31,         
    (Unaudited)    2008    2007    2006    2005        2004    2003 
     Per Share Operating Performance                                 
Net asset value, beginning of period    $ 14.30    $ 15.49    $ 15.89    $ 15.57    $ 16.04    $ 15.56    $ 15.34 
Net investment income1    0.45    0.71    1.01    1.01    1.05        1.08    1.11 
Net realized and unrealized gain (loss)    (0.81)    (1.18)    (0.40)    0.36    (0.35)        0.48    0.16 
Dividends to Preferred Shareholders from                                 
   net investment income    (0.11)    (0.22)    (0.32)    (0.27)    (0.19)        (0.08)    (0.07) 
Net increase (decrease) from investment operations    (0.47)    (0.69)    0.29    1.10    0.51        1.48    1.20 
Dividends to Common Shareholders from                                 
   net investment income    (0.32)    (0.50)    (0.69)    (0.78)    (0.96)        (1.00)    (0.98) 
Capital charges with respect to the issuance                                 
   of Preferred Shares                           (0.00)2    (0.02)             
Net asset value, end of period    $ 13.51    $ 14.30    $ 15.49    $ 15.89    $ 15.57    $ 16.04    $ 15.56 
Market price, end of period    $ 11.18    $ 12.43    $ 13.67    $ 14.60    $ 14.91    $ 15.61    $ 14.81 
 
     Total Investment Return3                                 
Based on net asset value    (2.63)%4    (4.18)%4    2.19%    7.52%    3.16%        10.15%    8.33% 
Based on market price    (7.30)%4    (5.62)%4    (1.85)%    3.16%    1.51%        12.63%    10.07% 
 
     Ratios to Average Net Assets Applicable to Common Shares                             
Total expenses after waiver and fees paid indirectly                                 
   and excluding interest expense and fees5,6    1.14%7    1.13%7    1.13%    1.13%    1.13%        1.05%    1.07% 
Total expenses after waiver and fees                                 
   paid indirectly6    1.52%7    1.48%7    1.72%    1.69%    1.69%        1.32%    1.29% 
Total expenses6    1.56%7    1.50%7    1.72%    1.70%    1.70%        1.33%    1.30% 
Net investment income6    6.78%7    6.18%7    6.44%    6.49%    6.56%        6.89%    7.08% 
Dividends paid to Preferred Shareholders    1.65%7    1.93%7    2.02%    1.76%    1.17%        0.51%    0.47% 
Net investment income to Common Shareholders    5.13%7    4.25%7    4.42%    4.73%    5.39%        6.38%    6.61% 
 
     Supplemental Data                                 
Net assets applicable to Common Shares,                                 
   end of period (000)    $ 155,119    $ 164,119    $ 177,807    $ 182,402    $ 178,771    $ 183,877    $ 178,337 
Preferred Shares outstanding at liquidation                                 
   preference, end of period (000)    $ 77,400    $ 77,400    $ 102,000    $ 102,000    $ 102,000    $ 88,000    $ 88,000 
Portfolio turnover    5%    24%    35%    25%    42%        41%    41% 
Asset coverage per Preferred Share, end of period    $ 75,106    $ 78,0188    $ 68,5858    $ 69,7178    $ 68,8278    $ 77,2418    $ 75,6668 

1 Based on average shares outstanding.
2 Amount is less than ($0.01) per share.
3 Total investment returns based on market value, which can be significantly greater
or lesser than the net asset value, may result in substantially different returns.
Total investment returns exclude the effects of sales charges.
4 Aggregate total investment return.

5 Interest expense and fees relate to tender option bond trusts. See Note 1 of
the Notes to Financial Statements for details of municipal bonds transferred to
tender option bond trusts.
6 Do not reflect the effect of dividends to Preferred Shareholders.
7 Annualized.
8 Prior year amounts have been recalculated to conform with current
year presentation.

See Notes to Financial Statements.

SEMI-ANNUAL REPORT

JANUARY 31, 2009

39


Notes to Financial Statements (Unaudited)

1. Organization and Significant Accounting Policies:

BlackRock MuniHoldings New Jersey Insured Fund, Inc. (“MuniHoldings
New Jersey Insured”), BlackRock MuniYield Insured Investment Fund
(formerly BlackRock MuniYield Florida Insured Fund) (“MuniYield Insured
Investment”), BlackRock MuniYield Michigan Insured Fund, Inc. (“MuniYield
Michigan Insured”), BlackRock MuniYield New Jersey Insured Fund, Inc.
(“MuniYield New Jersey Insured”) and BlackRock MuniYield Pennsylvania
Insured Fund (“MuniYield Pennsylvania Insured”) (the “Funds” or individ-
ually, as the “Fund”) are registered under the Investment Company Act
of 1940, as amended (the “1940 Act”), as non-diversified, closed-end
management investment companies. MuniHoldings New Jersey Insured,
MuniYield Michigan Insured and MuniYield New Jersey Insured are
organized as Maryland corporations. MuniYield Insured Investment and
MuniYield Pennsylvania Insured are organized as Massachusetts busi-
ness trusts. The Funds’ financial statements are prepared in conformity
with accounting principles generally accepted in the United States of
America, which may require the use of management accruals and esti-
mates. Actual results may differ from these estimates. The Funds deter-
mine and make available for publication the net asset value of
their Common Shares on a daily basis.

The following is a summary of significant accounting policies followed
by the Funds:

Valuation of Investments: Municipal investments (including commitments
to purchase such investments on a “when-issued” basis) are valued
on the basis of prices provided by dealers or pricing services selected
under the supervision of each Fund’s Board of Trustees or Directors (the
“Board”). In determining the value of a particular investment, pricing
services may use certain information with respect to transactions in such
investments, quotations from dealers, pricing matrixes, market trans-
actions in comparable investments and information with respect to
various relationships between investments. Swap agreements are valued
by utilizing quotes received daily by the Funds’ pricing service or through
brokers, which are derived using daily swap curves and trades of under-
lying securities. Short-term securities with maturities less than 60 days
are valued at amortized cost, which approximates fair value. Investments
in open-end investment companies are valued at net asset value each
business day.

In the event that application of these methods of valuation results in
a price for an investment which is deemed not to be representative of
the market value of such investment, the investment will be valued by
a method approved by each Fund’s Board as reflecting fair value (“Fair
Value Assets”). When determining the price for Fair Value Assets, the
investment advisor and/or sub-advisor seeks to determine the price that
each Fund might reasonably expect to receive from the current sale of

that asset in an arm’s-length transaction. Fair value determinations shall
be based upon all available factors that the investment advisor and/or
sub-advisor deems relevant. The pricing of all Fair Value Assets is subse-
quently reported to the Board or a committee thereof.

Derivative Financial Instruments: Each Fund may engage in various
portfolio investment strategies both to increase the return of the Fund
and to hedge, or protect, its exposure to interest rate movements and
movements in the securities markets. Losses may arise if the value of
the contract decreases due to an unfavorable change in the price of
the underlying security or if the counterparty does not perform under
the contract.

Forward Interest Rate Swaps — The Funds may enter into forward
interest rate swaps for investment purposes. The Funds may enter
into swap agreements, in which the Fund and a counterparty agree
to make periodic net payments on a specified notional amount.
In a forward interest rate swap, a Fund and the counterparty agree
to make periodic net payments on a specified notional contract
amount, commencing on a specified future effective date, unless
terminated earlier. These periodic payments received or made by the
Funds are recorded in the accompanying Statements of Operations
as realized gains or losses, respectively. Swaps are marked-to-market
daily and changes in value are recorded as unrealized appreciation
(depreciation). When the swap is terminated, the Funds will record
a realized gain or loss equal to the difference between the proceeds
from (or cost of) the closing transaction and the Funds’ basis in the
contract, if any. The Funds generally intend to close each forward
interest rate swap before the effective date specified in the agree-
ment and therefore avoid entering into the interest rate swap under-
lying each forward interest rate swap. Swap transactions involve,
to varying degrees, elements of credit and market risk in excess of
the amounts recognized on the Statements of Assets and Liabilities.
Such risks involve the possibility that there will be no liquid market
for these agreements, that the counterparty to the agreements may
default on its obligation to perform or disagree as to the meaning
of the contractual terms in the agreements, and that there may be
unfavorable changes in interest rates and/or market values associ-
ated with these transactions.

Forward Commitments and When-Issued Delayed Delivery Securities:
The Funds may purchase securities on a when-issued basis and may
purchase or sell securities on a forward commitment basis. Settlement
of such transactions normally occurs within a month or more after the
purchase or sale commitment is made. The Funds may purchase securi-
ties under such conditions only with the intention of actually acquiring

40 SEMI-ANNUAL REPORT

JANUARY 31, 2009


Notes to Financial Statements (continued)

them, but may enter into a separate agreement to sell the securities
before the settlement date. Since the value of securities purchased may
fluctuate prior to settlement, the Funds may be required to pay more at
settlement than the security is worth. In addition, the purchaser is not
entitled to any of the interest earned prior to settlement. When purchas-
ing a security on a delayed-delivery basis, the Funds assume the rights
and risks of ownership of the security, including the risk of price and
yield fluctuations.

Municipal Bonds Transferred to Tender Option Bond Trusts: The Funds
leverage their assets through the use of tender option bond trusts
(“TOBs”). A TOB is established by a third party sponsor forming a special
purpose entity, into which one or more funds, or an agent on behalf of
the funds, transfers municipal bonds. Other funds managed by the
investment advisor may also contribute municipal bonds to a TOB into
which the Fund has contributed securities. A TOB typically issues
two classes of beneficial interests: short-term floating rate certificates,
which are sold to third party investors, and residual certificates (“TOB
Residuals”), which are generally issued to the participating funds that
made the transfer. The TOB Residuals held by the Funds include the
right of the Funds (1) to cause the holders of a proportional share of
the floating rate certificates to tender their certificates at par, and (2) to
transfer, within seven days, a corresponding share of the municipal
bonds from the TOB to the Funds. The TOB may also be terminated with-
out the consent of the Funds upon the occurrence of certain events as
defined in the TOB agreements. Such termination events may include
the bankruptcy or default of the municipal bonds, a substantial down-
grade in credit quality of the municipal bonds, the inability of the TOB to
obtain quarterly or annual renewal of the liquidity support agreement, a
substantial decline in market value of the municipal bonds or the inabil-
ity to remarket the short-term floating rate certificates to third
party investors.

The cash received by the TOB from the sale of the short-term floating
rate certificates, less transaction expenses, is paid to the Fund, which
typically invests the cash in additional municipal bonds. The Funds’
transfer of the municipal bonds to a TOB is accounted for as a secured
borrowing, therefore the municipal bonds deposited into a TOB are pre-
sented in the Fund’s Schedule of Investments and the proceeds from the
issuance of the short-term floating rate certificates are shown on the
Statements of Assets and Liabilities as Trust Certificates.

Interest income from the underlying security is recorded by the Funds
on an accrual basis. Interest expense incurred on the secured borrowing
and other expenses related to remarketing, administration and trustee
services to a TOB are reported as expenses of the Funds. The floating

rate certificates have interest rates that generally reset weekly and their
holders have the option to tender certificates to the TOB for redemption
at par at each reset date. At January 31, 2009, the aggregate value of
the underlying municipal bonds transferred to TOBs, the related liability
for trust certificates and the range of interest rates on the liability for the
trust certificates were as follows:

    Underlying         
    Municipal         
    Bonds    Liability for    Range of 
    Transferred    Trust    Interest 
    to TOBs    Certificates    Rates 
MuniHoldings New Jersey            2.412% – 
   Insured    $25,988,960    $14,825,000    3.351% 
MuniYield Insured            2.153% – 
   Investment    $17,756,462    $ 8,490,632    2.830% 
MuniYield Michigan            2.242% – 
   Insured    $30,278,956    $16,190,000    2.630% 
MuniYield New Jersey            2.412% – 
   Insured    $ 9,983,616    $ 5,655,000    3.351% 
MuniYield Pennsylvania            1.838% – 
   Insured    $24,508,800    $11,000,000    2.561% 

Financial transactions executed through TOBs generally will underperform
the market for fixed rate municipal bonds when interest rates rise, but
tend to outperform the market for fixed rate bonds when interest rates
decline or remain relatively stable. Should short-term interest rates rise,
the Funds’ investments in TOBs may adversely affect the Funds’ invest-
ment income and distributions to Common Shareholders. Also, fluctua-
tions in the market value of municipal bonds deposited into the TOB may
adversely affect the Funds’ net asset value per share.

Zero-Coupon Bonds: The Funds may invest in zero-coupon bonds, which
are normally issued at a significant discount from face value and do not
provide periodic interest payments. Zero-coupon bonds may experience
greater volatility in market value than similar maturity debt obligations
which provide regular interest payments.

Segregation and Collateralization: In cases in which the 1940 Act and
the interpretive positions of the Securities and Exchange Commission
(“SEC”) require that each Fund segregates assets in connection with
certain investments (e.g., swaps), each Fund will, consistent with certain
interpretive letters issued by the SEC, designate on their books and
records cash or other liquid securities having a market value at least
equal to the amount that would otherwise be required to be physically
segregated. Furthermore, based on requirements and agreements with
certain exchanges and third party broker-dealers, the Funds may also be
required to deliver or deposit securities as collateral for certain invest-
ments (e.g., swaps).

SEMI-ANNUAL REPORT

JANUARY 31, 2009

41


Notes to Financial Statements (continued)

Investment Transactions and Investment Income: Investment trans-
actions are recorded on the dates the transactions are entered into
(the trade dates). Realized gains and losses on security transactions are
determined on the identified cost basis. Dividend income is recorded
on the ex-dividend dates. Interest income is recognized on the accrual
method. Each Fund amortizes all premiums and discounts on debt
securities.

Dividends and Distributions: Dividends from net investment income are
declared and paid monthly. Distributions of capital gains are recorded
on the ex-dividend dates. Dividends and distributions to Preferred
Shareholders are accrued and determined as described in Note 5.

Income Taxes: It is each Fund’s policy to comply with the requirements
of the Internal Revenue Code applicable to regulated investment com-
panies and to distribute substantially all of its taxable income to its
shareholders. Therefore, no federal income tax provision is required.

Each Fund files US federal and various state and local tax returns. No
income tax returns are currently under examination. The statute of limita-
tions on the Funds’ US federal tax returns remains open for each of the
four years ended July 31, 2008. The statutes of limitations on the Funds’
state and local tax returns may remain open for an additional year
depending upon the jurisdiction.

Recent Accounting Pronouncement: In March 2008, Statement of
Financial Accounting Standards No. 161, “Disclosures about Derivative
Instruments and Hedging Activities — an amendment of FASB Statement
No. 133” (“FAS 161”), was issued. FAS 161 is intended to improve
financial reporting for derivative instruments by requiring enhanced
disclosure that enables investors to understand how and why an entity
uses derivatives, how derivatives are accounted for, and how derivative
instruments affect an entity’s results of operations and financial position.
FAS 161 is effective for financial statements issued for fiscal years
and interim periods beginning after November 15, 2008. The impact
on the Funds’ financial statement disclosures, if any, is currently
being assessed.

Deferred Compensation and BlackRock Closed-End Share Equivalent
Investment Plan: Under the deferred compensation plan approved by
each Fund’s Board, non-interested Trustees or Directors (“Independent
Trustees”) may defer a portion of their annual complex-wide compensa-
tion. Deferred amounts earn an approximate return as though equivalent
dollar amounts had been invested in common shares of other certain
BlackRock Closed-End Funds selected by the Independent Trustees.
This has approximately the same economic effect for the Independent
Trustees as if the Independent Trustees had invested the deferred
amounts directly in the other certain BlackRock Closed-End Funds.

The deferred compensation plan is not funded and obligations there-
under represent general unsecured claims against the general assets
of each Fund. Each Fund may, however, elect to invest in common
shares of the other certain BlackRock Closed-End Funds selected by
the Independent Trustees in order to match its deferred compensation
obligations.

Other: Expenses directly related to each Fund are charged to that
Fund. Other operating expenses shared by several funds are pro-rated
among those funds on the basis of relative net assets or other appro-
priate methods.

2. Investment Advisory Agreement and Other Transactions
with Affiliates:

Each Fund entered into an Investment Advisory Agreement with BlackRock
Advisors, LLC (the “Advisor”), an indirect, wholly owned subsidiary of
BlackRock, Inc., to provide investment advisory and administration
services. As of January 31, 2009, The PNC Financial Services Group, Inc.
(“PNC”) and Bank of America Corporation (“BAC”) are the largest stock-
holders of BlackRock, Inc. (“BlackRock”). BAC became a stockholder of
BlackRock following its acquisition of Merrill Lynch & Co., Inc. (“Merrill
Lynch”) on January 1, 2009. Prior to that date, both PNC and Merrill
Lynch were considered affiliates of the Funds under the 1940 Act.
Subsequent the acquisition, PNC remains an affiliate, but due to the
restructuring of Merrill Lynch’s ownership interest of BlackRock, BAC
is not deemed to be an affiliate under the 1940 Act.

The Advisor is responsible for the management of each Fund’s portfolio
and provides the necessary personnel, facilities, equipment and certain
other services necessary to the operations of each Fund. For such ser-
vices, each Fund pays the Advisor a monthly fee at an annual rate of
0.50%, except MuniHoldings New Jersey Insured, which is 0.55%,
of each Fund’s average daily net assets. Average daily net assets is the
average daily value of each Fund’s total assets minus the sum of its
accrued liabilities.

The Advisor has voluntarily agreed to waive its advisory fee on the pro-
ceeds of Preferred Shares and TOBs that exceed 35% of the average
daily net assets of MuniHoldings New Jersey Insured. For the six months
ended January 31, 2009, the Advisor waived $168,191, which is
included in fees waived by advisor on the Statements of Operations.

The Advisor has agreed to waive its advisory fees by the amount of
investment advisory fees each Fund pays to the Advisor indirectly
through its investment in affiliated money market funds. This amount is
shown on the Statements of Operations as fees waived by advisor. For
the six months ended January 31, 2009, the amounts were as follows:

42 SEMI-ANNUAL REPORT

JANUARY 31, 2009


Notes to Financial Statements (continued)

    Fees Waived 
    by Advisor 
MuniHoldings New Jersey Insured    $14,577 
MuniYield Insured Investment    $17,308 
MuniYield Michigan Insured    $22,858 
MuniYield New Jersey Insured    $ 6,899 
MuniYield Pennsylvania Insured    $30,430 

The Advisor has entered into a separate sub-advisory agreement with
BlackRock Investment Management, LLC (“BIM”), an affiliate of the
Advisor, under which the Advisor pays BIM for services it provides, a
monthly fee that is a percentage of the investment advisory fee paid by
the Funds to the Advisor.

For the six months ended January 31, 2009, each Fund reimbursed the
Advisor for certain accounting services in the following amounts, which
are included in accounting services on the Statements of Operations:

    Amount 
MuniHoldings New Jersey Insured    $4,380 
MuniYield Insured Investment    $1,634 
MuniYield Michigan Insured    $3,499 
MuniYield New Jersey Insured    $1,838 
MuniYield Pennsylvania Insured    $2,243 

Certain officers and/or directors/trustees or directors of the Funds are
officers and/or directors of BlackRock, Inc. or its affiliates. The Funds
reimburse the Advisor for compensation paid to the Funds’ Chief
Compliance Officer.

3. Investments:

Purchases and sales of investments, excluding short-term securities, for
the six months ended January 31, 2009 were as follows:

    Purchases    Sales 
MuniHoldings New Jersey Insured    $26,041,045    $33,063,956 
MuniYield Insured Investment    $25,633,174    $34,918,395 
MuniYield Michigan Insured    $19,269,152    $60,921,401 
MuniYield New Jersey Insured    $ 7,953,481    $15,794,629 
MuniYield Pennsylvania Insured    $11,915,802    $41,579,281 

4. Concentration, Market and Credit Risk:

Each Fund invests a substantial amount of its assets in issuers located
in a single state or limited number of states. Please see each Fund’s
Schedule of Investments for concentrations in specific states.

Many municipalities insure repayment of their bonds, which reduces
risk of loss due to issuer default. The market value of these bonds may
fluctuate for other reasons, including market perception of the value of
such insurance, and there is no guarantee that the insurer will meet
its obligation.

In the normal course of business, the Funds invest in securities and
enter into transactions where risks exist due to fluctuations in the market
(market risk) or failure of the issuer of a security to meet all its obliga-
tions (credit risk). The value of securities held by the Funds may decline
in response to certain events, including those directly involving the
issuers whose securities are owned by the Funds; conditions affecting
the general economy; overall market changes; local, regional or global
political, social or economic instability; and currency and interest rate
and price fluctuations. Similar to credit risk, the Funds may be exposed
to counterparty risk, or the risk that an entity with which the Funds have
unsettled or open transactions may default. Financial assets, which
potentially expose the Funds to credit and counterparty risks, consist
principally of investments and cash due from counterparties. The extent
of the Funds’ exposure to credit and counterparty risks with respect to
these financial assets is approximated by their value recorded in each
Fund’s Statement of Assets and Liabilities.

5. Capital Share Transactions:

Common Shares

MuniYield Insured Investment and MuniYield Pennsylvania Insured
are authorized to issue an unlimited number of Common Shares of
beneficial interest, par value $0.10 per share together with 1,000,000
Preferred Shares of beneficial interest, par value of $0.05 per share.
The Funds’ Board is authorized, however, to classify and reclassify any
unissued shares of capital shares without approval of Common
Shareholders.

MuniHoldings New Jersey Insured, MuniYield Michigan Insured and
MuniYield New Jersey Insured are authorized to issue 200,000,000
shares, including Preferred Shares, par value $0.10 per share or $0.05
per share, all of which were initially classified as Common Shares. The
Funds’ Board is authorized, however, to classify and reclassify any
unissued shares of capital shares without approval of Common
Shareholders.

For MuniHoldings New Jersey Insured, shares issued and outstanding
during the six months ended January 31, 2009 and the year ended July
31, 2008 remained constant.

For MuniYield Insured Investment, MuniYield Michigan Insured, MuniYield
New Jersey Insured and MuniYield Pennsylvania Insured, shares issued
and outstanding during the six months ended January 31, 2009, the
period November 1, 2007 to July 31, 2008 and the year ended October
31, 2007 remained constant.

SEMI-ANNUAL REPORT

JANUARY 31, 2009

43


Notes to Financial Statements (continued)

Preferred Shares

The Preferred Shares are redeemable at the option of each Fund, in
whole or in part, on any dividend payment date at its liquidation prefer-
ence per share plus any accumulated unpaid dividends whether or not
declared. The Preferred Shares are also subject to mandatory redemp-
tion at $25,000 per share plus any accumulated or unpaid dividends,
whether or not declared, if certain requirements relating to the composi-
tion of the assets and liabilities of a Fund, as set forth in each Fund’s
Statement of Preferences/Articles of Incorporation, are not satisfied.

The holders of Preferred Shares have voting rights equal to the holders
of Common Shares (one vote per share) and will vote together with
holders of Common Shares (one vote per share) as a single class.
However, the holders of Preferred Shares, voting as a separate class,
are also entitled to elect two Directors/Trustees for each Fund. In addi-
tion, the 1940 Act requires that along with approval by shareholders that
might otherwise be required, the approval of the holders of a majority of
any outstanding Preferred Shares, voting separately as a class would be
required to (a) adopt any plan of reorganization that would adversely
affect the Preferred Shares, (b) change a Fund’s sub-classification as a
closed-end investment company or change its fundamental investment
restrictions or (c) change its business so as to cease to be an invest-
ment company.

The Funds had the following series of Preferred Shares outstanding and
effective yields as of January 31, 2009:

MuniHoldings New Jersey Insured         
    Shares    Yields 
Series A    1,1841    0.655% 
Series B    1,1841    0.716% 
Series C    2,0891    0.731% 
Series D    1,6361    0.746% 
Series E    9751    0.716% 
 
MuniYield Insured Investment         
    Shares    Yields 
Series A    2,0751    0.655% 
Series B    4152    1.778% 
 
MuniYield Michigan Insured         
    Shares    Yields 
Series A    1,7531    0.731% 
Series B    1,7531    0.716% 
Series C    1,4031    0.746% 
Series D    8772    1.695% 

MuniYield New Jersey Insured         
    Shares    Yields 
Series A    2,0021    0.716% 
Series B    6262    1.751% 
 
MuniYield Pennsylvania Insured         
    Shares    Yields 
Series A    1,2141    0.655% 
Series B    1,4571    0.731% 
Series C    4252    1.751% 

1 The maximum applicable rate on this series of Preferred Shares is the higher
of 110% of the AA commercial paper rate or 110% of 90% of the Kenny S&P
30-day High Grade Index rate divided by 1.00 minus the marginal tax rate.
2 The maximum applicable rate on this series of Preferred Shares is the higher
of 110% plus or times (i) the Telerate/BBA LIBOR or (ii) 90% of the Kenny S&P
30-day High Grade Index rate divided by 1.00 minus the marginal tax rate.

Each Fund’s series of Preferred Shares have a reset frequency of seven
days. Dividends on seven-day Preferred Shares are cumulative at a rate
that is reset every seven days based on the results of an auction. If
the Preferred Shares fail to clear the auction on an auction date, the
affected Fund is required to pay the maximum applicable rate on the
Preferred Shares to holders of such shares for successive dividend
periods until such time as the shares are successfully auctioned. The
maximum applicable rate on the Preferred Shares is footnoted as appli-
cable on the above chart. The low, high and average dividend
rates on the Preferred Shares for each Fund for the six months ended
January 31, 2009 were as follows:

MuniHoldings New Jersey Insured             
    Low    High    Average 
Series A    0.594%    10.205%    3.123% 
Series B    0.594%    12.261%    3.112% 
Series C    0.594%    11.347%    3.094% 
Series D    0.640%    12.565%    3.126% 
Series E    0.594%    11.728%    3.084% 
 
MuniYield Insured Investment             
    Low    High    Average 
Series A    0.594%    10.205%    3.081% 
Series B    1.682%    12.523%    3.862% 
 
MuniYield Michigan Insured             
    Low    High    Average 
Series A    0.594%    11.347%    3.099% 
Series B    0.594%    11.728%    3.142% 
Series C    0.640%    12.565%    3.128% 
Series D    1.640%    10.377%    3.928% 

44 SEMI-ANNUAL REPORT

JANUARY 31, 2009


Notes to Financial Statements (continued)

MuniYield New Jersey Insured             
    Low    High    Average 
Series A    0.594%    11.728%    3.095% 
Series B    1.640%    12.246%    3.848% 
 
MuniYield Pennsylvania Insured             
    Low    High    Average 
Series A    0.594%    10.205%    3.113% 
Series B    0.594%    11.347%    3.094% 
Series C    1.640%    12.246%    3.905% 

For the six months ended January 31, 2009, the Preferred Shares of
each Fund failed to clear any of their auctions. As a result, the Preferred
Share dividend rates were reset to the maximum applicable rate, which
ranged from 0.594% to 12.565% . A failed auction is not an event of
default for the Funds but it has a negative impact on the liquidity of the
Preferred Shares. A failed auction occurs when there are more sellers of
a fund’s auction rate Preferred Shares than buyers. It is impossible to
predict how long this imbalance will last. A successful auction for each
Fund’s Preferred Shares may not occur for some time, if ever, and even
if liquidity does resume, Preferred Shareholders may not have the ability
to sell the Preferred Shares at their liquidation preference.

A Fund may not declare dividends or make other distributions on
Common Shares or purchase any such shares if, at the time of the
declaration, distribution or purchase, asset coverage with respect to the
outstanding Preferred Shares is less than 200%.

Prior to December 22, 2008, the Funds paid commissions to certain
broker-dealers at the end of each auction at an annual rate of 0.25%,
calculated on the aggregate principal amount. As of December 22,
2008, commissions paid to broker-dealers on preferred shares that
experienced a failed auction were reduced to 0.15% on the aggregate
principal amount. The Funds will continue to pay commissions of 0.25%
on the aggregate principal amount of all shares that successfully clear
their auctions. Merrill Lynch, Pierce, Fenner & Smith Incorporated
(“MLPF&S”), a wholly owned subsidiary of Merrill Lynch, earned com-
missions for the period August 1, 2008 through December 31, 2008
as follows. Subsequent to that date, neither MLPF&S or Merrill Lynch
are considered affiliates of the Funds.

    Commissions 
MuniHoldings New Jersey Insured    $ 231,521 
MuniYield Insured Investment    $ 95,353 
MuniYield Michigan Insured    $ 174,537 
MuniYield New Jersey Insured    $ 93,868 
MuniYield Pennsylvania Insured    $ 124,097 

Shares issued and outstanding during the six months ended January 31,
2009 remained constant.

During the year ended July 31, 2008, the Funds announced the follow-
ing redemptions of Preferred Shares at a price of $25,000 per share
plus any accrued and unpaid dividends through the redemption date:

MuniHoldings    Redemption    Shares to be    Aggregate 
New Jersey Insured    Date    Redeemed    Price 
Series A    6/24/2008    176    $ 4,400,000 
Series B    6/27/2008    176    $ 4,400,000 
Series C    6/25/2008    311    $ 7,775,000 
Series D    6/26/2008    244    $ 6,100,000 
Series E    6/23/2008    145    $ 3,625,000 
 
MuniYield    Redemption    Shares to be    Aggregate 
Insured Investment    Date    Redeemed    Price 
Series A    6/24/2008    325    $ 8,125,000 
Series B    6/26/2008    65    $ 1,625,000 
 
MuniYield    Redemption    Shares to be    Aggregate 
Michigan Insured    Date    Redeemed    Price 
Series A    6/25/2008    247    $ 6,175,000 
Series B    6/23/2008    247    $ 6,175,000 
Series C    6/26/2008    197    $ 4,925,000 
Series D    6/24/2008    123    $ 3,075,000 
 
MuniYield    Redemption    Shares to be    Aggregate 
New Jersey Insured    Date    Redeemed    Price 
Series A    6/23/2008    238    $ 5,950,000 
Series B    6/27/2008    74    $ 1,850,000 
 
MuniYield    Redemption    Shares to be    Aggregate 
Pennsylvania Insured    Date    Redeemed    Price 
Series A    6/24/2008    386    $ 9,650,000 
Series B    6/25/2008    463    $11,575,000 
Series C    6/27/2008    135    $ 3,375,000 

6. Capital Loss Carryforward:

As of July 31, 2008, certain Funds had a capital loss carryforward
available to offset future realized capital gains through the indicated year
of expiration:

        MuniYield     
    MuniHoldings    Insured    MuniYield 
    New Jersey    Investment    Michigan 
Expires July 31,    Insured    Fund    Insured 
2009    $22,843,109         
2010            $1,124,652 
2011    235,894         
2012        $2,081,725    3,953,220 
2016        659,619    1,689,814 
Total    $23,079,003    $2,741,344    $6,767,686 

SEMI-ANNUAL REPORT

JANUARY 31, 2009

45


Notes to Financial Statements (concluded)

7. Restatement Information (For MuniYield Michigan
Insured):

Subsequent to the initial issuance of MuniYield Michigan Insured’s
October 31, 2006 financial statements, the Fund determined that the
criteria for sale accounting in FAS 140 had not been met for certain
transfers of municipal bonds and that these transfers should have been
accounted for as secured borrowings rather than as sales. As a result,
certain financial highlights for each of the three years in the period
ended October 31, 2005 have been restated to give effect to recording
the transfers of the municipal bonds as secured borrowings, including
recording interest on the bonds as interest income and interest on the
secured borrowings as interest expense.

Financial Highlights for MuniYield Michigan Insured             
Years Ended October 31, 2005, 2004 and 2003             
 
    2005    2004        2003     
    Previously        Previously        Previously     
    Reported    Restated    Reported                 Restated    Reported                 Restated 
Total expenses                         
   after waiver5    1.10%    1.42%    1.00%    1.19%    1.01%    1.20% 
Total expenses5    1.10%    1.42%    1.02%    1.22%    1.03%    1.21% 
Portfolio turnover    30.16%    25%    36.63%    32%    33.39%    29% 
 
   5 Do not reflect the effect of dividends to Preferred Shareholders.     

8. Subsequent Events:

The Funds paid a net investment income dividend in the following
amounts per share on March 2, 2009 to shareholders of record on
February 13, 2009:

    Common 
    Dividend 
    Per Share 
MuniHoldings New Jersey Insured    $ 0.0530 
MuniYield Insured Investment    $ 0.0535 
MuniYield Michigan Insured    $ 0.0540 
MuniYield New Jersey Insured    $ 0.0540 
MuniYield Pennsylvania Insured    $ 0.0530 

The dividends declared on Preferred Shares for the period February 1,
2009 to February 28, 2009 for the Funds were as follows:

    Series    Dividend Declared 
MuniHoldings New Jersey Insured    A    $16,723 
    B    $17,379 
    C    $29,526 
    D    $24,057 
    E    $13,876 

 
 
MuniYield Insured Investment    A    $29,308 
    B    $14,302 

 
 
MuniYield Michigan Insured    A    $24,777 
    B    $24,948 
    C    $20,642 
    D    $29,783 

 
 
MuniYield New Jersey Insured    A    $28,492 
    B    $21,574 

 
 
MuniYield Pennsylvania Insured    A    $17,147 
    B    $20,594 
    C    $14,647 

46 SEMI-ANNUAL REPORT

JANUARY 31, 2009


Officers and Directors/Trustees

Richard E. Cavanagh, Chairman of the Board and Director/Trustee
Karen . Robards, Vice Chair of the Board, Chair of the
Audit Committee and Director/Trustee
G. Nicholas Beckwith, III, Director/Trustee
Richard S. Davis, Fund President1 and Director/Trustee
Kent Dixon, Director/Trustee
Frank J. Fabozzi, Director/Trustee
Kathleen F. Feldstein, Director/Trustee
James T. Flynn, Director/Trustee
Henry Gabbay, Director/Trustee
Jerrold B. Harris, Director/Trustee
R. Glenn Hubbard, Director/Trustee
W. Carl Kester, Director/Trustee
Donald C. Burke, Fund President2 and Chief Executive Officer
Anne F. Ackerley, Vice President
Neal J. Andrews, Chief Financial Officer
Jay M. Fife, Treasurer
Brian . Kindelan, Chief Compliance Officer of the Funds
Howard B. Surloff, Secretary

1 Fund President of BlackRock MuniYield Insured Investment Fund and BlackRock
MuniYield Pennsylvania Insured Fund

2 Fund President for BlackRock MuniHoldings New Jersey Insured Fund, Inc.,
BlackRock MuniYield Michigan Insured Fund, Inc. and BlackRock MuniYield New
Jersey Insured Fund, Inc.

BlackRock MuniYield Pennsylvania Insured Fund

Custodian
State Street Bank and Trust Company
Boston, MA 02101

Transfer Agent Auction Agent
Common Shares: Preferred Shares:
Computershare Trust BNY Mellon Shareowner Services
Company, N.A. Jersey City, NJ 07310
Providence, RI 02940

BlackRock MuniHoldings New Jersey Insured Fund, Inc.
BlackRock MuniYield Insured Investment Fund
BlackRock MuniYield Michigan Insured Fund, Inc.
BlackRock MuniYield New Jersey Insured Fund, Inc.

Custodian
The Bank of New York Mellon
New York, NY 10286

Transfer Agent and Auction Agent
Common Shares and Preferred Shares:
BNY Mellon Shareowner Services
Jersey City, NJ 07310

For All Funds:

Accounting Agent
State Street Bank and Trust Company
Princeton, NJ 08540

Independent Registered Public
Accounting Firm
Deloitte & Touche LLP
Princeton, NJ 08540

Legal Counsel
Skadden, Arps, Slate, Meagher & Flom LLP
New York, NY 10036

Effective January 1, 2009, Robert S. Salomon, Jr. retired as
Director/Trustee of the Funds. The Board wishes Mr. Salomon
well in his retirement.

SEMI-ANNUAL REPORT JANUARY 31, 2009 47


Additional Information

Proxy Results

The Annual Meeting of Shareholders was held on September 12, 2008 for shareholders of record on July 14, 2008 to elect director/trustee
nominees of each Fund/Trust:

Approved the Directors/Trustees as follows:                         
    G. Nicholas Beckwith, III    Kent Dixon    R. Glenn Hubbard 
        Votes         Votes        Votes 
     Votes For    Withheld    Votes For    Withheld    Votes For    Withheld 
BlackRock MuniHoldings New Jersey                         
   Insured Fund, Inc.    19,165,778    943,880    19,160,014     949,644    19,143,575               966,083 
BlackRock MuniYield Insured Investment                         
   Fund    7,339,151    464,982    7,336,151     467,982    7,348,020               456,113 
BlackRock MuniYield Michigan Insured                         
   Fund, Inc.    16,174,236    840,544    16,172,632     842,148    16,173,497               841,283 
BlackRock MuniYield New Jersey Insured                         
   Fund, Inc.    8,026,547    202,984    8,025,169     204,362    8,026,178               203,353 
BlackRock MuniYield Pennsylvania                         
   Insured Fund    10,705,364    372,929    10,701,363     376,930    10,704,985               373,308 
 
    W. Carl Kester    Robert S. Salomon, Jr.    Richard S. Davis 
        Votes         Votes        Votes 
     Votes For    Withheld    Votes For    Withheld    Votes For    Withheld 
BlackRock MuniHoldings New Jersey                         
   Insured Fund, Inc.    5,0541    1,7321    19,158,623     951,035    19,153,934               955,724 
BlackRock MuniYield Insured Investment                         
   Fund    2,1671    01    7,339,151     464,982    7,348,020               456,113 
BlackRock MuniYield Michigan Insured                         
   Fund, Inc.    5,3461    3891    16,173,083     841,697    16,181,223               833,557 
BlackRock MuniYield New Jersey Insured                         
   Fund, Inc.    1,6661    6131    8,026,169     203,362    8,024,598               204,933 
BlackRock MuniYield Pennsylvania                         
   Insured Fund    2,7881    2461    10,700,300     377,993    10,705,364               372,929 
 
               Frank J. Fabozzi    James T. Flynn    Karen P. Robards 
        Votes         Votes        Votes 
     Votes For    Withheld    Votes For    Withheld    Votes For    Withheld 
BlackRock MuniHoldings New Jersey                         
   Insured Fund, Inc.    5,0541    1,7321    19,133,505     976,153    19,170,085               939,573 
BlackRock MuniYield Insured Investment                         
   Fund    2,1671    01    7,345,020     459,113    7,348,020               456,113 
BlackRock MuniYield Michigan Insured                         
   Fund, Inc.    5,3461    3891    16,175,897     838,883    16,177,074               837,706 
BlackRock MuniYield New Jersey Insured                         
   Fund, Inc.    1,6661    6131    8,024,539     204,992    8,028,177               201,354 
BlackRock MuniYield Pennsylvania                         
   Insured Fund    2,7881    2461    10,699,313     378,980    10,703,211               375,082 
 
   1 Voted on by holders of Preferred Shares only.                         

48 SEMI-ANNUAL REPORT

JANUARY 31, 2009


Additional Information (continued)                     
 
Proxy Results (concluded)                         
 
    Richard E. Cavanagh    Kathleen F. Feldstein               Henry Gabbay 
         Votes         Votes         Votes 
    Votes For    Withheld    Votes For    Withheld    Votes For    Withheld 
BlackRock MuniHoldings New Jersey                         
   Insured Fund, Inc.    19,183,246     926,412    19,127,496     982,162    19,161,767     947,891 
BlackRock MuniYield Insured Investment                         
   Fund    7,348,020     456,113    7,336,151     467,982    7,348,020     456,113 
BlackRock MuniYield Michigan Insured                         
   Fund, Inc.    16,180,873     833,907    16,167,456     847,324    16,179,503     835,277 
BlackRock MuniYield New Jersey Insured                         
   Fund, Inc.    8,028,177     201,354    8,028,177     201,354    8,028,178     201,353 
BlackRock MuniYield Pennsylvania                         
   Insured Fund    10,703,314     374,979    10,698,360     379,933    10,704,964     373,329 
 
    Jerrold B. Harris                 
         Votes                 
    Votes For    Withheld                 
BlackRock MuniHoldings New Jersey                         
   Insured Fund, Inc.    19,183,246     926,412                 
BlackRock MuniYield Insured Investment                         
   Fund    7,339,151     464,982                 
BlackRock MuniYield Michigan Insured                         
   Fund, Inc.    16,175,023     839,757                 
BlackRock MuniYield New Jersey Insured                         
   Fund, Inc.    8,028,178     201,353                 
BlackRock MuniYield Pennsylvania                         
   Insured Fund    10,700,863     377,430                 

Dividend Policy

The Funds’ dividend policy is to distribute all or a portion of their net
investment income to its shareholders on a monthly basis. In order to
provide shareholders with a more stable level of dividend distributions,
the Funds may at times pay out less than the entire amount of net
investment income earned in any particular month and may at times
in any particular month pay out such accumulated but undistributed
income in addition to net investment income earned in that month.

As a result, the dividends paid by the Funds for any particular month
may be more or less than the amount of net investment income earned
by the Funds during such month. The Funds’ current accumulated
but undistributed net investment income, if any, is disclosed in the
Statements of Assets and Liabilities, which comprises part of the
financial information included in this report.

SEMI-ANNUAL REPORT

JANUARY 31, 2009

49


Additional Information (continued)

General Information

The Funds will mail only one copy of shareholder documents, including
annual and semi-annual reports and proxy statements, to shareholders
with multiple accounts at the same address. This practice is commonly
called “householding” and it is intended to reduce expenses and elimi-
nate duplicate mailings of shareholder documents. Mailings of your
shareholder documents may be householded indefinitely unless you
instruct us otherwise. If you do not want the mailing of these documents
to be combined with those for other members of your household, please
contact the Funds at (800) 441-7762.

Quarterly performance, semi-annual and annual reports and other
information regarding the Funds may be found on BlackRock’s website,
which can be accessed at http://www.blackrock.com. This reference
to BlackRock’s website is intended to allow investors public access to
information regarding the Funds and does not, and is not intended to,
incorporate BlackRock’s website into this report.

Availability of Quarterly Schedule of Investments

The Funds file their complete schedule of portfolio holdings with
the SEC for the first and third quarters of each fiscal year on
Form N-Q. The Funds’ Forms N-Q are available on the SEC’s website
at http://www.sec.gov and may also be reviewed and copied at the

SEC’s Public Reference Room in Washington, DC. Information on the
operation of the Public Reference Room may be obtained by calling
(800) SEC-0330. The Funds’ Forms N-Q may also be obtained upon
request and without charge by calling (800) 441-7762.

Electronic Delivery

Electronic copies of most financial reports are available on the Funds’
websites or shareholders can sign up for e-mail notifications of quarterly
statements, annual and semi-annual reports by enrolling in the Funds’
electronic delivery program.

Shareholders Who Hold Accounts with Investment Advisors, Banks
or Brokerages:

Please contact your financial advisor to enroll. Please note that not all
investment advisors, banks or brokerages may offer this service.

Section 19 Notices

The amounts and sources of distributions reported are only estimates and
are not being provided for tax reporting purposes. The actual amounts and
sources for tax reporting purposes will depend upon each Fund’s invest-
ment experience during the year and may be subject to changes based

on the tax regulations. Each Fund will send you a Form 1099-DIV each
calendar year that will tell you how to report these distributions for federal
income tax purposes.

         Total Fiscal Year-to-Date            Percentage of Fiscal Year-to-Date     
    Cumulative Distributions by Character    Cumulative Distributions by Character 
 
    Net    Net Realized        Total Per    Net    Net Realized        Total Per 
    Investment    Capital    Return of    Common    Investment    Capital    Return of    Common 
    Income    Gains    Capital    Share    Income    Gains    Capital    Share 
BlackRock MuniYield Insured Investment Fund    $0.329            $0.329    100%    0%    0%    100% 
BlackRock MuniYield New Jersey Insured Fund, Inc    $0.324    $0.017        $0.341    95%    5%    0%    100% 

50 SEMI-ANNUAL REPORT

JANUARY 31, 2009


Additional Information (concluded)

Board Approvals

On September 12, 2008, the Board of Directors of the Funds voted
unanimously to change certain investment guidelines of the Funds. Under
normal market conditions, the Funds are required to invest at least 80%
of their total assets in municipal bonds either (i) insured under an insur-
ance policy purchased by the Funds or (ii) insured under an insurance
policy obtained by the issuer of the municipal bond or any other party.
Historically, the Funds have had an additional non-fundamental invest-
ment policy limiting its purchase of insured municipal bonds to those
bonds insured by insurance providers with claims-paying abilities rated
AAA or Aaa at the time of investment.

Following the onset of the credit and liquidity crises currently troubling
the financial markets, the applicable rating agencies lowered the claims-
paying ability rating of most of the municipal bond insurance providers
below the highest rating category. As a result, the Advisor recommended,
and the Board approved, an amended policy with respect to the pur-
chase of insured municipal bonds that such bonds must be insured by
insurance providers or other entities with claims-paying abilities rated
at least investment grade. This investment grade restriction is measured
at the time of investment, and the Funds will not be required to dispose
of municipal bonds they hold in the event of subsequent downgrades.
The approved changes do not alter the Funds’ investment objectives.

In addition, on September 12, 2008, the Board of Directors of
BlackRock MuniYield Florida Insured Fund voted unanimously to change
a non-fundamental investment policy of the Fund, and to rename the
Fund “BlackRock MuniYield Insured Investment Fund.” The Fund’s previ-
ous non-fundamental investment policy required the Fund, under normal
market conditions, to invest at least 80% of its assets in Florida municipal
bonds insured by insurers with claims-paying abilities rated AAA at time
of investment. Due to the repeal of the Florida Intangible Personal Property
Tax as of January 2007, the Board has approved an amended policy
allowing the Fund flexibility to invest in municipal obligations regardless

of geographic location, as well as revising the policy with respect to
the claims-paying ability rating adopted by the Fund. The Fund's new
investment policy is, under normal market conditions, to invest at least
80% of its assets in municipal bonds insured by insurers or other
entities with claims-paying abilities rated at least investment grade
at time of investment. The approved changes will not alter the Fund’s
investment objective.

Under current market conditions, the Advisor anticipates that it will
gradually reposition the BlackRock MuniYield Insured Investment Fund’s
portfolio over time and that during such period, the Fund may continue
to hold a substantial portion of its assets in Florida municipal bonds. At
this time, it is uncertain how long the repositioning may take, and the
Fund will continue to be subject to risks associated with investing a
significant portion of its assets in Florida municipal bonds until the
repositioning is complete.

The Advisor and the Board believe the amended policies will allow the
Advisor to better manage the Funds’ portfolios in the best interests of the
Funds’ shareholders and to better meet the Funds' investment objectives.

Effective September 13, 2008, following approval by the Funds’ Board
and the applicable ratings agencies, the Board amended the terms of
the Funds’ Statement of Preferences/Articles of Incorporation in order
to allow the Funds to enter into TOB transactions, the proceeds of
which were used to redeem a portion of the Funds’ Preferred Shares.
Accordingly, the definition of Inverse Floaters was amended to incorporate
the Funds’ permissible ratio of floating rate instruments into inverse float-
ing rate instruments. Additionally, confirming changes and certain formula
modifications concerning inverse floaters were made to the definitions
of Moody’s Discount Factor and S&P Discount Factor, as applicable, to
integrate the Funds’ investments in TOBs into applicable calculations.

SEMI-ANNUAL REPORT

JANUARY 31, 2009

51



This report is transmitted to shareholders only. It is not a prospec-
tus. Past performance results shown in this report should not be
considered a representation of future performance. The Funds have
leveraged their Common Shares, which creates risks for Common
Shareholders, including the likelihood of greater volatility of net
asset value and market price of the Common Shares, and the risk
that fluctuations in the short-term dividend rates of the Preferred
Shares, currently set at the maximum reset rate as a result of
failed auctions, may affect the yield to Common Shareholders.
Statements and other information herein are as dated and are
subject to change.

A description of the policies and procedures that the Funds use
to determine how to vote proxies relating to portfolio securities
is available (1) without charge, upon request, by calling toll-free
(800) 441-7762; (2) at www.blackrock.com; and (3) on the Secu-
rities and Exchange Commission’s website at http://www.sec.gov.
Information about how the Funds voted proxies relating to securities
held in the Funds’ portfolios during the most recent 12-month
period ended June 30 is available upon request and without charge
(1) at www.blackrock.com or by calling (800) 441-7762 and
(2) on the Securities and Exchange Commission’s website at
http://www.sec.gov.

BlackRock MuniHoldings New Jersey Insured Fund, Inc.

BlackRock MuniYield Insured Investment Fund

BlackRock MuniYield Michigan Insured Fund, Inc.

BlackRock MuniYield New Jersey Insured Fund, Inc.

BlackRock MuniYield Pennsylvania Insured Fund

100 Bellevue Parkway

Wilmington, DE 19809

#MHMYINS6-1/09


Item 2 – Code of Ethics – Not Applicable to this semi-annual report

Item 3 – Audit Committee Financial Expert – Not Applicable to this semi-annual report

Item 4 – Principal Accountant Fees and Services – Not Applicable to this semi-annual report

Item 5 – Audit Committee of Listed Registrants – Not Applicable to this semi-annual report

Item 6 – Investments
(a) The registrant’s Schedule of Investments is included as part of the Report to
Stockholders filed under Item 1 of this form.
(b) Not Applicable due to no such divestments during the semi-annual period covered since
the previous Form N-CSR filing.

Item 7 – Disclosure of Proxy Voting Policies and Procedures for Closed-End Management
Investment Companies – Not Applicable to this semi-annual report

Item 8 – Portfolio Managers of Closed-End Management Investment Companies – Not Applicable to
this semi-annual report

Item 9 – Purchases of Equity Securities by Closed-End Management Investment Company and
Affiliated Purchasers – Not Applicable

Item 10 – Submission of Matters to a Vote of Security Holders – The registrant’s Nominating and
Governance Committee will consider nominees to the board of directors recommended by
shareholders when a vacancy becomes available. Shareholders who wish to recommend a
nominee should send nominations that include biographical information and set forth the
qualifications of the proposed nominee to the registrant’s Secretary. There have been no
material changes to these procedures.

Item 11 – Controls and Procedures

11(a) – The registrant’s principal executive and principal financial officers or persons performing
similar functions have concluded that the registrant’s disclosure controls and procedures (as
defined in Rule 30a-3(c) under the Investment Company Act of 1940, as amended (the
“1940 Act”)) are effective as of a date within 90 days of the filing of this report based on the
evaluation of these controls and procedures required by Rule 30a-3(b) under the 1940 Act
and Rule 13(a)-15(b) under the Securities Exchange Act of 1934, as amended.

11(b) – There were no changes in the registrant’s internal control over financial reporting (as
defined in Rule 30a-3(d) under the 1940 Act) that occurred during the second fiscal quarter
of the period covered by this report that have materially affected, or are reasonably likely to
materially affect, the registrant’s internal control over financial reporting.

Item 12 – Exhibits attached hereto

12(a)(1) – Code of Ethics – Not Applicable to this semi-annual report

12(a)(2) – Certifications – Attached hereto

12(a)(3) – Not Applicable

12(b) – Certifications – Attached hereto


Pursuant to the requirements of the Securities Exchange Act of 1934 and the Investment
Company Act of 1940, the registrant has duly caused this report to be signed on its behalf by
the undersigned, thereunto duly authorized.

BlackRock MuniYield Insured Investment Fund

By: /s/ Donald C. Burke
Donald C. Burke
Chief Executive Officer of
BlackRock MuniYield Insured Investment Fund

Date: March 25, 2009

Pursuant to the requirements of the Securities Exchange Act of 1934 and the Investment
Company Act of 1940, this report has been signed below by the following persons on behalf
of the registrant and in the capacities and on the dates indicated.

By: /s/ Donald C. Burke
Donald C. Burke
Chief Executive Officer (principal executive officer) of
BlackRock MuniYield Insured Investment Fund

Date: March 25, 2009

By: /s/ Neal J. Andrews
Neal J. Andrews
Chief Financial Officer (principal financial officer) of
BlackRock MuniYield Insured Investment Fund

Date: March 25, 2009