<TABLE> <S> <C>

<PAGE>

<ARTICLE> 5

<S>                             <C>                     <C>                     <C>
<PERIOD-TYPE>                   YEAR                   YEAR                   YEAR
<FISCAL-YEAR-END>                          DEC-31-1996             DEC-31-1995             DEC-31-1994
<PERIOD-START>                             JAN-01-1996             JAN-01-1995             JAN-01-1994
<PERIOD-END>                               DEC-31-1996             DEC-31-1995             DEC-31-1994
<CASH>                                          19,817                   7,490                   4,021
<SECURITIES>                                    12,727                   8,544                  10,311
<RECEIVABLES>                                   55,540                  33,509                  21,087
<ALLOWANCES>                                     1,085                     787                     552
<INVENTORY>                                          0                       0                       0
<CURRENT-ASSETS>                               105,399                  60,477                  40,269
<PP&E>                                          30,690                  18,588                   9,659
<DEPRECIATION>                                  11,663                   6,546                   3,633
<TOTAL-ASSETS>                                 130,400                  77,546                  52,051
<CURRENT-LIABILITIES>                           36,917                  25,642                  18,473
<BONDS>                                              0                       0                       0
<PREFERRED-MANDATORY>                                0                       0                       0
<PREFERRED>                                          0                       0                       0
<COMMON>                                           484                     456                     445
<OTHER-SE>                                           0                       0                       0
<TOTAL-LIABILITY-AND-EQUITY>                   130,400                  77,546                  52,051
<SALES>                                              0                       0                       0
<TOTAL-REVENUES>                               236,554                 156,266                  94,287
<CGS>                                                0                       0                       0
<TOTAL-COSTS>                                  201,941                 135,745                  82,017
<OTHER-EXPENSES>                                 (648)                 (1,727)                   (326)
<LOSS-PROVISION>                                   298                     235                      91
<INTEREST-EXPENSE>                                  46                     365                     154
<INCOME-PRETAX>                                 35,215                  21,883                  12,526
<INCOME-TAX>                                    14,115                   8,535                   4,604
<INCOME-CONTINUING>                             21,100                  13,348                   7,922
<DISCONTINUED>                                       0                       0                       0
<EXTRAORDINARY>                                      0                       0                       0
<CHANGES>                                            0                       0                       0
<NET-INCOME>                                    21,100                  13,348                   7,922
<EPS-PRIMARY>                                     0.39                    0.25                    0.16
<EPS-DILUTED>                                     0.39                    0.25                    0.16


</TABLE>