WARNING: THE EDGAR SYSTEM ENCOUNTERED ERROR(S) WHILE PROCESSING THIS SCHEDULE.
<TABLE> <S> <C>
<ARTICLE> 6
<CIK> 0000917469
<NAME> LOOMIS SAYLES & COMPANY, L.P.
<SERIES>
<NUMBER> 02
<NAME> LSIT FIXED INCOME FUND
<S> <C>
<PERIOD-TYPE> 12-MOS
<FISCAL-YEAR-END> SEP-30-2000
<PERIOD-START> OCT-01-1999
<PERIOD-END> SEP-30-2000
<INVESTMENTS-AT-COST> 445055079
<INVESTMENTS-AT-VALUE> 414571772
<RECEIVABLES> 18006774
<ASSETS-OTHER> 0
<OTHER-ITEMS-ASSETS> 834706
<TOTAL-ASSETS> 433413252
<PAYABLE-FOR-SECURITIES> 5329814
<SENIOR-LONG-TERM-DEBT> 0
<OTHER-ITEMS-LIABILITIES> 353650
<TOTAL-LIABILITIES> 5683464
<SENIOR-EQUITY> 0
<PAID-IN-CAPITAL-COMMON> 437972847
<SHARES-COMMON-STOCK> 35803108
<SHARES-COMMON-PRIOR> 24638993
<ACCUMULATED-NII-CURRENT> 23473198
<OVERDISTRIBUTION-NII> 0
<ACCUMULATED-NET-GAINS> 0
<OVERDISTRIBUTION-GAINS> (3224230)
<ACCUM-APPREC-OR-DEPREC> (30492027)
<NET-ASSETS> 427729788
<DIVIDEND-INCOME> 1203111
<INTEREST-INCOME> 31953129
<OTHER-INCOME> 0
<EXPENSES-NET> (2330665)
<NET-INVESTMENT-INCOME> 30825575
<REALIZED-GAINS-CURRENT> (2673519)
<APPREC-INCREASE-CURRENT> (7502115)
<NET-CHANGE-FROM-OPS> 20649941
<EQUALIZATION> 0
<DISTRIBUTIONS-OF-INCOME> (24292627)
<DISTRIBUTIONS-OF-GAINS> 0
<DISTRIBUTIONS-OTHER> 0
<NUMBER-OF-SHARES-SOLD> 10967383
<NUMBER-OF-SHARES-REDEEMED> (1889932)
<SHARES-REINVESTED> 2086664
<NET-CHANGE-IN-ASSETS> 129722429
<ACCUMULATED-NII-PRIOR> 17609095
<ACCUMULATED-GAINS-PRIOR> 0
<OVERDISTRIB-NII-PRIOR> 0
<OVERDIST-NET-GAINS-PRIOR> (1219556)
<GROSS-ADVISORY-FEES> 1847489
<INTEREST-EXPENSE> 0
<GROSS-EXPENSE> 2330665
<AVERAGE-NET-ASSETS> 369497727
<PER-SHARE-NAV-BEGIN> 12.09
<PER-SHARE-NII> 0.78
<PER-SHARE-GAIN-APPREC> (0.09)
<PER-SHARE-DIVIDEND> (0.83)
<PER-SHARE-DISTRIBUTIONS> 0.00
<RETURNS-OF-CAPITAL> 0.00
<PER-SHARE-NAV-END> 11.95
<EXPENSE-RATIO> 0.63
[AVG-DEBT-OUTSTANDING] 0
[AVG-DEBT-PER-SHARE] 0
</TABLE>