<TABLE> <S> <C>
<ARTICLE> 6
<CIK> 0000088498
<NAME> SECURITY INCOME FUND
<SERIES>
<NUMBER> 051
<NAME> HIGH YIELD - A
<MULTIPLIER> 1,000
<CURRENCY> U.S. DOLLARS
<S> <C>
<PERIOD-TYPE> 6-MOS
<FISCAL-YEAR-END> DEC-31-2000
<PERIOD-START> JAN-01-2000
<PERIOD-END> JUN-30-2000
<EXCHANGE-RATE> 1.000
<INVESTMENTS-AT-COST> 10202
<INVESTMENTS-AT-VALUE> 8623
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<TOTAL-ASSETS> 11073
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<SENIOR-LONG-TERM-DEBT> 0
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<TOTAL-LIABILITIES> 233
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<PAID-IN-CAPITAL-COMMON> 12696
<SHARES-COMMON-STOCK> 511
<SHARES-COMMON-PRIOR> 464
<ACCUMULATED-NII-CURRENT> (4)
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<OVERDISTRIBUTION-GAINS> 0
<ACCUM-APPREC-OR-DEPREC> (1579)
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<INTEREST-INCOME> 487
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<EXPENSES-NET> 56
<NET-INVESTMENT-INCOME> 436
<REALIZED-GAINS-CURRENT> (273)
<APPREC-INCREASE-CURRENT> (392)
<NET-CHANGE-FROM-OPS> (229)
<EQUALIZATION> 0
<DISTRIBUTIONS-OF-INCOME> (277)
<DISTRIBUTIONS-OF-GAINS> 0
<DISTRIBUTIONS-OTHER> 0
<NUMBER-OF-SHARES-SOLD> 71
<NUMBER-OF-SHARES-REDEEMED> (44)
<SHARES-REINVESTED> 20
<NET-CHANGE-IN-ASSETS> 217
<ACCUMULATED-NII-PRIOR> 2
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<OVERDISTRIB-NII-PRIOR> 0
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<PER-SHARE-NAV-BEGIN> 13.65
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<PER-SHARE-NAV-END> 12.82
<EXPENSE-RATIO> .74
</TABLE>
