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<PAGE> PAGE 16
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<PAGE> PAGE 19
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<TABLE> <S> <C>
<ARTICLE> 6
<CIK> 0000356682
<NAME> CALVERT SOCIAL INVESTMENT FUND
<SERIES>
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<NAME> EQUITY PORTFOLIO, CLASS B
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<S> <C>
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<PERIOD-START> APR-01-1998
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</TABLE>
<TABLE> <S> <C>
<ARTICLE> 6
<CIK> 0000356682
<NAME> CALVERT SOCIAL INVESTMENT FUND
<SERIES>
<NUMBER> 144
<NAME> EQUITY PORTFOLIO, CLASS C
<MULTIPLIER> 1000
<S> <C>
<PERIOD-TYPE> YEAR
<FISCAL-YEAR-END> SEP-30-1998
<PERIOD-START> APR-01-1998
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</TABLE>
<TABLE> <S> <C>
<ARTICLE> 6
<CIK> 0000356682
<NAME> CALVERT SOCIAL INVESTMENT FUND
<SERIES>
<NUMBER> 145
<NAME> MANAGED INDEX PORTFOLIO, CLASS A
<MULTIPLIER> 1000
<S> <C>
<PERIOD-TYPE> YEAR
<FISCAL-YEAR-END> SEP-30-1998
<PERIOD-START> APR-01-1998
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</TABLE>
<TABLE> <S> <C>
<ARTICLE> 6
<CIK> 0000356682
<NAME> CALVERT SOCIAL INVESTMENT FUND
<SERIES>
<NUMBER> 146
<NAME> MANAGED INDEX PORTFOLIO, CLASS B
<MULTIPLIER> 1000
<S> <C>
<PERIOD-TYPE> YEAR
<FISCAL-YEAR-END> SEP-30-1998
<PERIOD-START> APR-01-1998
<PERIOD-END> SEP-30-1998
<INVESTMENTS-AT-COST> 22173
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</TABLE>
<TABLE> <S> <C>
<ARTICLE> 6
<CIK> 0000356682
<NAME> CALVERT SOCIAL INVESTMENT FUND
<SERIES>
<NUMBER> 147
<NAME> MANAGED INDEX PORTFOLIO, CLASS C
<MULTIPLIER> 1000
<S> <C>
<PERIOD-TYPE> YEAR
<FISCAL-YEAR-END> SEP-30-1998
<PERIOD-START> APR-01-1998
<PERIOD-END> SEP-30-1998
<INVESTMENTS-AT-COST> 22173
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</TABLE>
<TABLE> <S> <C>
<ARTICLE> 6
<CIK> 0000356682
<NAME> CALVERT SOCIAL INVESTMENT FUND
<SERIES>
<NUMBER> 148
<NAME> MANAGED INDEX PORTFOLIO, CLASS I
<MULTIPLIER> 1000
<S> <C>
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<FISCAL-YEAR-END> SEP-30-1998
<PERIOD-START> APR-01-1998
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<AVERAGE-NET-ASSETS> 15896
<PER-SHARE-NAV-BEGIN> 15.00
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</TABLE>
