WARNING: THE EDGAR SYSTEM ENCOUNTERED ERROR(S) WHILE PROCESSING THIS SCHEDULE.

<TABLE> <S> <C>

<ARTICLE> 6
<CIK> 0000862502
<NAME> National Intermediate Municipal Fund
<SERIES>
   <NUMBER>005
   <NAME>The Salomon Brothers Investment Series

<S>                             <C>
<PERIOD-TYPE>                  6-MOS
<FISCAL-YEAR-END>                               Dec-31-2000
<PERIOD-END>                                    Jun-30-2000
<INVESTMENTS-AT-COST>                            10,947,044
<INVESTMENTS-AT-VALUE>                           11,112,346
<RECEIVABLES>                                       297,396
<ASSETS-OTHER>                                       29,858
<OTHER-ITEMS-ASSETS>                                      0
<TOTAL-ASSETS>                                   11,439,600
<PAYABLE-FOR-SECURITIES>                                  0
<SENIOR-LONG-TERM-DEBT>                                   0
<OTHER-ITEMS-LIABILITIES>                           129,671
<TOTAL-LIABILITIES>                                 129,671
<SENIOR-EQUITY>                                           0
<PAID-IN-CAPITAL-COMMON>                         11,258,797
<SHARES-COMMON-STOCK>                               333,177
<SHARES-COMMON-PRIOR>                               439,258
<ACCUMULATED-NII-CURRENT>                           (53,959)
<OVERDISTRIBUTION-NII>                                    0
<ACCUMULATED-NET-GAINS>                             (60,211)
<OVERDISTRIBUTION-GAINS>                                  0
<ACCUM-APPREC-OR-DEPREC>                            165,302
<NET-ASSETS>                                     11,309,929
<DIVIDEND-INCOME>                                         0
<INTEREST-INCOME>                                   350,542
<OTHER-INCOME>                                            0
<EXPENSES-NET>                                       66,216
<NET-INVESTMENT-INCOME>                             284,326
<REALIZED-GAINS-CURRENT>                            (15,107)
<APPREC-INCREASE-CURRENT>                            46,299
<NET-CHANGE-FROM-OPS>                               315,518
<EQUALIZATION>                                            0
<DISTRIBUTIONS-OF-INCOME>                            98,931
<DISTRIBUTIONS-OF-GAINS>                                  0
<DISTRIBUTIONS-OTHER>                                     0
<NUMBER-OF-SHARES-SOLD>                             254,854
<NUMBER-OF-SHARES-REDEEMED>                         368,518
<SHARES-REINVESTED>                                   7,583
<NET-CHANGE-IN-ASSETS>                           (1,964,550)
<ACCUMULATED-NII-PRIOR>                             (54,031)
<ACCUMULATED-GAINS-PRIOR>                           (45,104)
<OVERDISTRIB-NII-PRIOR>                                   0
<OVERDIST-NET-GAINS-PRIOR>                                0
<GROSS-ADVISORY-FEES>                                35,347
<INTEREST-EXPENSE>                                        0
<GROSS-EXPENSE>                                     160,280
<AVERAGE-NET-ASSETS>                              4,203,836
<PER-SHARE-NAV-BEGIN>                                10.150
<PER-SHARE-NII>                                       0.240
<PER-SHARE-GAIN-APPREC>                               0.030
<PER-SHARE-DIVIDEND>                                  0.240
<PER-SHARE-DISTRIBUTIONS>                             0.000
<RETURNS-OF-CAPITAL>                                  0.000
<PER-SHARE-NAV-END>                                  10.180
<EXPENSE-RATIO>                                        0.75



</TABLE>