<ARTICLE>                     5
<LEGEND>
This schedule contains summary financial information extracted from Swift Energy
Managed Pension Assets Partnership 1990-B, Ltd.'s balance sheet and statement of
operations contained in its Form 10-K for the year ended December 31, 1996.
</LEGEND>
       
                             
<PERIOD-TYPE>                   YEAR
<FISCAL-YEAR-END>                              DEC-31-1996
<PERIOD-END>                                   DEC-31-1996
<CASH>                                         31,415
<SECURITIES>                                   0
<RECEIVABLES>                                  125,196
<ALLOWANCES>                                   0
<INVENTORY>                                    0
<CURRENT-ASSETS>                               156,611
<PP&E>                                         4,134,626
<DEPRECIATION>                                 (3,174,638)
<TOTAL-ASSETS>                                 1,116,599
<CURRENT-LIABILITIES>                          3,983
<BONDS>                                        0
<PREFERRED-MANDATORY>                          0
<PREFERRED>                                    0
<COMMON>                                       0
<OTHER-SE>                                     1,112,616
<TOTAL-LIABILITY-AND-EQUITY>                   1,116,599
<SALES>                                        511,189
<TOTAL-REVENUES>                               512,385
<CGS>                                          0
<TOTAL-COSTS>                                  219,475<F1>
<OTHER-EXPENSES>                               0
<LOSS-PROVISION>                               0
<INTEREST-EXPENSE>                             0
<INCOME-PRETAX>                                230,634
<INCOME-TAX>                                   0
<INCOME-CONTINUING>                            230,634
<DISCONTINUED>                                 0
<EXTRAORDINARY>                                0
<CHANGES>                                      0
<NET-INCOME>                                   230,634
<EPS-PRIMARY>                                  0
<EPS-DILUTED>                                  0
<FN>
<F1>Includes lease operating expenses, production taxes and depreciation,
depletion and amortization expense.  excludes general and administrative and 
interest expense.
</FN>