WARNING: THE EDGAR SYSTEM ENCOUNTERED ERROR(S) WHILE PROCESSING THIS SCHEDULE.
<TABLE> <S> <C>
<ARTICLE> 6
<CIK> 0000894632
<NAME> PAINEWEBBER SECURITIES TRUS
<SERIES>
<NUMBER> 2
<NAME> PAINEWEBBER SMALL CAP FUND CLASS B
<MULTIPLIER> 1000
<S> <C>
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<FISCAL-YEAR-END> JUL-31-2000
<PERIOD-START> AUG-01-1999
<PERIOD-END> JUL-31-2000
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<NET-INVESTMENT-INCOME> (261)
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<APPREC-INCREASE-CURRENT> (287)
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<NET-CHANGE-IN-ASSETS> (3,313)
<ACCUMULATED-NII-PRIOR> 0
<ACCUMULATED-GAINS-PRIOR> (2,008)
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<PER-SHARE-NAV-BEGIN> 10.36
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</TABLE>