<ARTICLE> 5 <LEGEND> This schedule contains summary financial information extracted from Swift Energy Income Partners 1988-C, Ltd.'s balance sheet and statement of operations contained in its Form 10-Q for the quarter ended June 30, 1999 and is qualified in its entirety by reference to such financial statements. </LEGEND> <PERIOD-TYPE> 6-MOS <FISCAL-YEAR-END> DEC-31-1999 <PERIOD-END> JUN-30-1999 <CASH> 75,229 <SECURITIES> 0 <RECEIVABLES> 30,816 <ALLOWANCES> 0 <INVENTORY> 0 <CURRENT-ASSETS> 106,045 <PP&E> 4,783,414 <DEPRECIATION> (4,314,403) <TOTAL-ASSETS> 581,535 <CURRENT-LIABILITIES> 22,464 <BONDS> 0 <PREFERRED-MANDATORY> 0 <PREFERRED> 0 <COMMON> 0 <OTHER-SE> 536,938 <TOTAL-LIABILITY-AND-EQUITY> 581,535 <SALES> 71,541 <TOTAL-REVENUES> 72,312 <CGS> 0 <TOTAL-COSTS> 49,440<F1> <OTHER-EXPENSES> 0 <LOSS-PROVISION> 0 <INTEREST-EXPENSE> 0 <INCOME-PRETAX> (4,261) <INCOME-TAX> 0 <INCOME-CONTINUING> (4,261) <DISCONTINUED> 0 <EXTRAORDINARY> 0 <CHANGES> 0 <NET-INCOME> (4,261) <EPS-BASIC> 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>