WARNING: THE EDGAR SYSTEM ENCOUNTERED ERROR(S) WHILE PROCESSING THIS SCHEDULE.
<TABLE> <S> <C>
<ARTICLE> 6
<LEGEND>
MSDW S&P 500 INDEX FUND - CLASS B
</LEGEND>
<S> <C>
<PERIOD-TYPE> 12-MOS
<FISCAL-YEAR-END> AUG-31-2000
<PERIOD-END> AUG-31-2000
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<INVESTMENTS-AT-VALUE> 2,521,304,830
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<PAID-IN-CAPITAL-COMMON> 1,966,951,682
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<DISTRIBUTIONS-OF-GAINS> (4,247,416)
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<NUMBER-OF-SHARES-REDEEMED> (32,840,732)
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</TABLE>
