<TABLE> <S> <C>
<ARTICLE> 6
<CIK> 0000741375
<NAME> MAS FUNDS
<SERIES>
<NUMBER> 181
<NAME> SPECIAL PURPOSE FIXED INCOME PORTFOLIO, INSTITUTIONAL CLASS
<MULTIPLIER> 1,000
<S> <C>
<PERIOD-TYPE> 12-MOS
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<PERIOD-START> OCT-01-1999
<PERIOD-END> SEP-30-2000
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<SHARES-COMMON-PRIOR> 40,599
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<REALIZED-GAINS-CURRENT> (5,986)
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<EQUALIZATION> 0
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<NUMBER-OF-SHARES-REDEEMED> (10,249)
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<NET-CHANGE-IN-ASSETS> (30,347)
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<OVERDIST-NET-GAINS-PRIOR> (13,203)
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</TABLE>
