<TABLE> <S> <C>

<PAGE>
 
<ARTICLE> 5
<LEGEND>
This schedule contains summary financial information extracted from the
financial statements of National Surgery Centers for the periods ended
March 31, 1996, June 30, 1996 and September 30, 1996 and is qualified
in its entirety by reference to such financial statemtents.
</LEGEND>
<RESTATED> 
       
<S>                             <C>                     <C>                     <C>
<PERIOD-TYPE>                   3-MOS                   6-MOS                   9-MOS
<FISCAL-YEAR-END>                          DEC-31-1996             DEC-31-1996             DEC-31-1996
<PERIOD-START>                             JAN-01-1996             JAN-01-1996             JAN-01-1996
<PERIOD-END>                               MAR-31-1996             JUN-30-1996             SEP-30-1996
<CASH>                                      13,360,000               8,308,000               9,167,000
<SECURITIES>                                 5,150,000                 250,000                 250,000
<RECEIVABLES>                               12,377,000              14,921,000              13,835,000
<ALLOWANCES>                                 1,645,000               1,700,000               1,570,000
<INVENTORY>                                  2,253,000               2,529,000               2,441,000
<CURRENT-ASSETS>                            32,816,000              26,184,000              25,837,000
<PP&E>                                      38,867,000              43,018,000              43,176,000
<DEPRECIATION>                               7,635,000               8,781,000               9,838,000
<TOTAL-ASSETS>                              89,981,000              94,669,000              95,163,000
<CURRENT-LIABILITIES>                       13,376,000              16,540,000              18,232,000
<BONDS>                                     21,837,000              19,660,000              15,234,000
<PREFERRED-MANDATORY>                                0                       0                       0
<PREFERRED>                                          0                       0                       0
<COMMON>                                        56,000                  88,000                  91,000
<OTHER-SE>                                  49,487,000              51,512,000              54,833,000
<TOTAL-LIABILITY-AND-EQUITY>                89,981,000              94,669,000              95,163,000
<SALES>                                     16,159,000              35,911,000              56,012,000
<TOTAL-REVENUES>                            16,159,000              35,911,000              56,012,000
<CGS>                                       12,907,000              28,068,000              43,939,000
<TOTAL-COSTS>                               12,907,000              28,068,000              43,939,000
<OTHER-EXPENSES>                               296,000               1,145,000               1,848,000
<LOSS-PROVISION>                               553,000               1,265,000                       0
<INTEREST-EXPENSE>                             592,000               1,297,000               2,011,000
<INCOME-PRETAX>                              2,364,000               5,401,000               8,214,000
<INCOME-TAX>                                   909,000               2,108,000               3,217,000
<INCOME-CONTINUING>                          1,455,000               3,293,000               4,997,000
<DISCONTINUED>                                       0                       0                       0
<EXTRAORDINARY>                                      0                       0                       0
<CHANGES>                                            0                       0                       0
<NET-INCOME>                                 1,455,000               3,293,000               4,997,000
<EPS-PRIMARY>                                      .11                     .26                     .37
<EPS-DILUTED>                                      .11                     .24                     .35
        

</TABLE>