<TABLE> <S> <C>

<PAGE>
<ARTICLE> 5
<LEGEND>
THIS SCHEDULE CONTAINS SUMMARY FINANCIAL INFORMATION EXTRACTED FROM THE
COMPANY'S FORM 10-Q FOR THE PERIOD ENDED SEPTEMBER 30, 1997 AND IS QUALIFIED IN
ITS ENTIRETY BY REFERENCE TO SUCH FINANCIAL STATEMENTS.
</LEGEND>
<RESTATED> 
<MULTIPLIER> 1,000
       
<S>                             <C>                     <C>
<PERIOD-TYPE>                   3-MOS                   9-MOS
<FISCAL-YEAR-END>                          DEC-31-1997             DEC-31-1997
<PERIOD-START>                             JUL-01-1997             JAN-01-1997
<PERIOD-END>                               SEP-30-1997             SEP-30-1997
<CASH>                                           8,915                       0
<SECURITIES>                                    48,226                       0
<RECEIVABLES>                                   16,850                       0
<ALLOWANCES>                                     1,145                       0
<INVENTORY>                                          0                       0
<CURRENT-ASSETS>                                76,859                       0
<PP&E>                                          15,765                       0
<DEPRECIATION>                                   5,891                       0
<TOTAL-ASSETS>                                  87,188                       0
<CURRENT-LIABILITIES>                           21,785                       0
<BONDS>                                              0                       0
<PREFERRED-MANDATORY>                                0                       0
<PREFERRED>                                          0                       0
<COMMON>                                            14                       0
<OTHER-SE>                                      65,389                       0
<TOTAL-LIABILITY-AND-EQUITY>                    87,188                       0
<SALES>                                         14,215                  37,284
<TOTAL-REVENUES>                                19,669                  52,016
<CGS>                                              678                   1,475
<TOTAL-COSTS>                                    3,844                  10,042
<OTHER-EXPENSES>                                13,218                  36,478
<LOSS-PROVISION>                                   448                     302
<INTEREST-EXPENSE>                                   4                      36
<INCOME-PRETAX>                                  3,071                   6,957
<INCOME-TAX>                                     1,044                   2,366
<INCOME-CONTINUING>                              2,027                   4,591
<DISCONTINUED>                                       0                       0
<EXTRAORDINARY>                                      0                       0
<CHANGES>                                            0                       0
<NET-INCOME>                                     2,027                   4,591
<EPS-PRIMARY>                                      .14                     .32
<EPS-DILUTED>                                      .14                     .31
        

</TABLE>