<TABLE> <S> <C>
<ARTICLE> 6
<CIK> 0000898031
<NAME> LORD ABBETT SECURITIES TRUST
<SERIES>
<NUMBER> 071
<NAME> MICRO-CAP GROWTH SERIES - CLASS Y
<S> <C>
<PERIOD-TYPE> 6-MOS
<FISCAL-YEAR-END> OCT-31-2000
<PERIOD-END> APR-30-2000
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</TABLE>