WARNING: THE EDGAR SYSTEM ENCOUNTERED ERROR(S) WHILE PROCESSING THIS SCHEDULE.
<TABLE> <S> <C>
<ARTICLE> 6
<CIK> 0000866700
<NAME> Federated Municipal Securities Income Trust
<SERIES>
<NUMBER> 012
<NAME> Federated Pennsylvania Municipal Income Fund- Class B Shares
<S> <C>
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[AVG-DEBT-OUTSTANDING] 0
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</TABLE>
