<TABLE> <S> <C>

<PAGE>
 
<ARTICLE> 5
<LEGEND>
This schedule contains summary financial information extracted from the
company's consolidated financial statements included in the Form 10-K for the
year ened December 31, 1998.
</LEGEND>
<MULTIPLIER> 1,000
       
<S>                             <C>                     <C>
<PERIOD-TYPE>                   YEAR                   YEAR
<FISCAL-YEAR-END>                          DEC-31-1998             DEC-31-1997<F1>
<PERIOD-START>                             JAN-01-1998             JAN-01-1997
<PERIOD-END>                               DEC-31-1998             DEC-31-1997
<CASH>                                          73,595                  89,829
<SECURITIES>                                       612                   2,348
<RECEIVABLES>                                  132,424                 105,513
<ALLOWANCES>                                    10,002                   7,817
<INVENTORY>                                          0                       0
<CURRENT-ASSETS>                               359,229                 322,532
<PP&E>                                         133,097                  86,374
<DEPRECIATION>                                  52,702                  40,244
<TOTAL-ASSETS>                                 695,660                 452,346
<CURRENT-LIABILITIES>                          313,873                 309,248
<BONDS>                                              0                       0
<PREFERRED-MANDATORY>                                0                       0
<PREFERRED>                                          0                       0
<COMMON>                                            71                      68
<OTHER-SE>                                     357,303                 118,193
<TOTAL-LIABILITY-AND-EQUITY>                   695,660                 452,346
<SALES>                                        815,303                 612,039
<TOTAL-REVENUES>                               815,303                 612,039
<CGS>                                          554,057                 430,245
<TOTAL-COSTS>                                  554,057                 430,245
<OTHER-EXPENSES>                               211,539                 200,949
<LOSS-PROVISION>                                     0                       0
<INTEREST-EXPENSE>                               4,068                   4,795
<INCOME-PRETAX>                                 51,127                 (20,438)
<INCOME-TAX>                                    28,321                   4,916
<INCOME-CONTINUING>                             22,806                 (25,354)
<DISCONTINUED>                                       0                  (1,507)
<EXTRAORDINARY>                                      0                       0
<CHANGES>                                            0                       0
<NET-INCOME>                                    22,806                 (26,861)
<EPS-PRIMARY>                                     0.33                   (0.42)
<EPS-DILUTED>                                     0.32                   (0.42)
<FN>
<F1>Restated
</FN>
        

</TABLE>