<TABLE> <S> <C>

<ARTICLE> 6
<CIK> 0000880583
<NAME> MFS Research Portfolio
<SERIES>
   <NUMBER>019
   <NAME>The Travelers Series Trust

<S>                             <C>
<PERIOD-TYPE>                  6-MOS
<FISCAL-YEAR-END>                               Dec-31-2000
<PERIOD-END>                                    Jun-30-2000
<INVESTMENTS-AT-COST>                           192,360,875
<INVESTMENTS-AT-VALUE>                          216,205,927
<RECEIVABLES>                                     1,824,594
<ASSETS-OTHER>                                       83,586
<OTHER-ITEMS-ASSETS>                                      0
<TOTAL-ASSETS>                                  218,114,107
<PAYABLE-FOR-SECURITIES>                          1,311,528
<SENIOR-LONG-TERM-DEBT>                                   0
<OTHER-ITEMS-LIABILITIES>                           206,474
<TOTAL-LIABILITIES>                               1,518,002
<SENIOR-EQUITY>                                           0
<PAID-IN-CAPITAL-COMMON>                        180,613,615
<SHARES-COMMON-STOCK>                            15,896,523
<SHARES-COMMON-PRIOR>                            11,648,150
<ACCUMULATED-NII-CURRENT>                            69,425
<OVERDISTRIBUTION-NII>                                    0
<ACCUMULATED-NET-GAINS>                          12,068,456
<OVERDISTRIBUTION-GAINS>                                  0
<ACCUM-APPREC-OR-DEPREC>                         23,844,609
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<DIVIDEND-INCOME>                                   571,218
<INTEREST-INCOME>                                   256,462
<OTHER-INCOME>                                            0
<EXPENSES-NET>                                      873,815
<NET-INVESTMENT-INCOME>                             (46,135)
<REALIZED-GAINS-CURRENT>                         12,371,550
<APPREC-INCREASE-CURRENT>                        (1,388,698)
<NET-CHANGE-FROM-OPS>                            10,936,717
<EQUALIZATION>                                            0
<DISTRIBUTIONS-OF-INCOME>                                 0
<DISTRIBUTIONS-OF-GAINS>                          3,136,681
<DISTRIBUTIONS-OTHER>                                     0
<NUMBER-OF-SHARES-SOLD>                           4,562,071
<NUMBER-OF-SHARES-REDEEMED>                         545,701
<SHARES-REINVESTED>                                 232,003
<NET-CHANGE-IN-ASSETS>                           64,523,055
<ACCUMULATED-NII-PRIOR>                                   0
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<OVERDISTRIB-NII-PRIOR>                                   0
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<INTEREST-EXPENSE>                                        0
<GROSS-EXPENSE>                                     873,815
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<PER-SHARE-NAV-BEGIN>                                13.060
<PER-SHARE-NII>                                       0.000
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<RETURNS-OF-CAPITAL>                                  0.000
<PER-SHARE-NAV-END>                                  13.630
<EXPENSE-RATIO>                                        0.96



</TABLE>