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<PAGE> PAGE 3
011 C030001 10048
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012 B000001 84-1785
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<PAGE> PAGE 4
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022 B000006 13-2518466
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022 B000007 36-3595942
022 C000007 133781
022 D000007 0
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022 B000008 13-3112953
022 C000008 118060
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022 B000009 13-1912900
022 C000009 84310
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022 B000010 13-5659485
022 C000010 82005
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<PAGE> PAGE 5
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SIGNATURE BARRY FINK
TITLE VICE PRESIDENT
<TABLE> <S> <C>
<ARTICLE> 6
<LEGEND>
MORGAN STANLEY DEAN WITTER U.S. GOVERNMENT MONEY MARKET TRUST
</LEGEND>
<CIK> 0000356409
<NAME> MSDW U.S. GOVERNMENT MONEY MARKET TRUST
<S> <C>
<PERIOD-TYPE> 6-MOS
<FISCAL-YEAR-END> JAN-31-1999
<PERIOD-END> JUL-31-1999
<INVESTMENTS-AT-COST> 1,037,612,434
<INVESTMENTS-AT-VALUE> 1,037,612,434
<RECEIVABLES> 280,227
<ASSETS-OTHER> 99,273
<OTHER-ITEMS-ASSETS> 0
<TOTAL-ASSETS> 1,037,991,934
<PAYABLE-FOR-SECURITIES> 0
<SENIOR-LONG-TERM-DEBT> 0
<OTHER-ITEMS-LIABILITIES> (6,742,668)
<TOTAL-LIABILITIES> (6,742,668)
<SENIOR-EQUITY> 0
<PAID-IN-CAPITAL-COMMON> 1,031,247,744
<SHARES-COMMON-STOCK> 1,031,247,745
<SHARES-COMMON-PRIOR> 1,017,463,124
<ACCUMULATED-NII-CURRENT> 1,522
<OVERDISTRIBUTION-NII> 0
<ACCUMULATED-NET-GAINS> 0
<OVERDISTRIBUTION-GAINS> 0
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<OTHER-INCOME> 0
<EXPENSES-NET> (4,387,938)
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<REALIZED-GAINS-CURRENT> 0
<APPREC-INCREASE-CURRENT> 0
<NET-CHANGE-FROM-OPS> 20,815,558
<EQUALIZATION> 0
<DISTRIBUTIONS-OF-INCOME> (20,815,675)
<DISTRIBUTIONS-OF-GAINS> 0
<DISTRIBUTIONS-OTHER> 0
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<NUMBER-OF-SHARES-REDEEMED> (1,073,547,790)
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<NET-CHANGE-IN-ASSETS> 13,784,503
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<ACCUMULATED-GAINS-PRIOR> 0
<OVERDISTRIB-NII-PRIOR> 0
<OVERDIST-NET-GAINS-PRIOR> 0
<GROSS-ADVISORY-FEES> (2,294,383)
<INTEREST-EXPENSE> 0
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<PER-SHARE-NAV-BEGIN> 1.00
<PER-SHARE-NII> .02
<PER-SHARE-GAIN-APPREC> 0
<PER-SHARE-DIVIDEND> (0.02)
<PER-SHARE-DISTRIBUTIONS> 0
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<PER-SHARE-NAV-END> 1.00
<EXPENSE-RATIO> .86
</TABLE>
ITEM 77M: Mergers
Morgan Stanley Dean Witter
U.S. Government Money Market Trust
On August 19, 1998 a Special Meeting of
Shareholders of the U.S. Government Money Market Series
("U.S. Government Money Market"), one of eleven portfolios
of Dean Witter Retirement Series ("Retirement Series"), was
held to consider and vote upon an Agreement and Plan of
Reorganization (the "Agreement and Plan") between Retirement
Series, on behalf of U.S. Government Money Market, and
Morgan Stanley Dean Witter U.S. Government Money Market
Trust ("the Acquiring Fund"), pursuant to which
substantially all of the assets of U.S. Government Money
Market would be combined with those of the Acquiring Fund
and shareholders of U.S. Government Money Market would
become shareholders of the Acquiring Fund receiving shares
of the Acquiring Fund with a value equal to the value of
their holdings in U.S. Government Money Market (the
"Reorganization").
On April 30, 1998, the Board of Trustees
unanimously approved the Reorganization Agreement, and on
August 19, 1998, the Agreement and Plan was approved by the
affirmative vote of a majority of the shares of U.S.
Government Money Market represented in person or by proxy
and entitled to vote at the meeting.
On September 11, 1998, the Reorganization Plan
between U.S. Government Money Market and the Acquiring Fund
was completed according to the terms set forth above and in
the Agreement and Plan. On
November 25, 1998, Retirement Series filed an application
with the Commission on Form N8-F for an Order declaring that
Retirement Series has ceased to be an investment company,
which application was amended on March 5, 1999. On April
21, 1999, the SEC issued an order pursuant to Section 8F of
the Investment Company Act of 1940 declaring that Retirement
Series ceased to be an investment company.
EXHIBIT
MORGAN STANLEY DEAN WITTER U.S. GOVERNMENET MONEY MARKET
TRUST
Sub-Item
77P Information Required to be Filed Pursuant to
Existing Exemptive Orders
(A) Statement Pursuant to Exemptive Order (ICA Release
No. 12207)
Pertaining to Amortized Cost Pricing
No action was taken during the period pursuant to
condition 2 (c) of the above-captioned Order.
