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<PAGE> PAGE 2
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<PAGE> PAGE 3
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<PAGE> PAGE 4
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<PAGE> PAGE 5
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<PAGE> PAGE 6
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<PAGE> PAGE 7
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SIGNATURE PAUL BUCUVALAS
TITLE MANAGING DIRECTOR
WARNING: THE EDGAR SYSTEM ENCOUNTERED ERROR(S) WHILE PROCESSING THIS SCHEDULE.
<TABLE> <S> <C>
<ARTICLE> 6
<LEGEND>
Putnam Money Market Fund
</LEGEND>
<SERIES>
<NUMBER> 4
<NAME> Class A
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<PERIOD-TYPE> SEMI
<FISCAL-YEAR-END> SEP-30-1999
<PERIOD-END> MAR-31-2000
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<PER-SHARE-NAV-END> 1.00
<EXPENSE-RATIO> .25
[AVG-DEBT-OUTSTANDING] 0
[AVG-DEBT-PER-SHARE] 0
</TABLE>
WARNING: THE EDGAR SYSTEM ENCOUNTERED ERROR(S) WHILE PROCESSING THIS SCHEDULE.
<TABLE> <S> <C>
<ARTICLE> 6
<LEGEND>
Putnam Money Market Fund
</LEGEND>
<SERIES>
<NUMBER> 4
<NAME> Class B
<S> <C>
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[AVG-DEBT-OUTSTANDING] 0
[AVG-DEBT-PER-SHARE] 0
</TABLE>
WARNING: THE EDGAR SYSTEM ENCOUNTERED ERROR(S) WHILE PROCESSING THIS SCHEDULE.
<TABLE> <S> <C>
<ARTICLE> 6
<LEGEND>
Putnam Money Market Fund
</LEGEND>
<SERIES>
<NUMBER> 4
<NAME> Class C
<S> <C>
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[AVG-DEBT-OUTSTANDING] 0
[AVG-DEBT-PER-SHARE] 0
</TABLE>
WARNING: THE EDGAR SYSTEM ENCOUNTERED ERROR(S) WHILE PROCESSING THIS SCHEDULE.
<TABLE> <S> <C>
<ARTICLE> 6
<LEGEND>
Putnam Money Market Fund
</LEGEND>
<SERIES>
<NUMBER> 4
<NAME> Class M
<S> <C>
<PERIOD-TYPE> SEMI
<FISCAL-YEAR-END> SEP-30-1999
<PERIOD-END> MAR-31-2000
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</TABLE>
