<TABLE> <S> <C>

<PAGE>
 
<ARTICLE> 5
<RESTATED>
       
<S>                             <C>                     <C>                     <C>
<PERIOD-TYPE>                    3-MOS                    6-MOS                    9-MOS          
<FISCAL-YEAR-END>                          MAR-31-1997             MAR-31-1997             MAR-31-1997
<PERIOD-START>                             APR-01-1996             APR-01-1996             APR-01-1996
<PERIOD-END>                               JUN-30-1996             SEP-30-1996             DEC-31-1996
<CASH>                                         112,771                 126,864                 300,830
<SECURITIES>                                    66,406                  60,543                  63,091
<RECEIVABLES>                                   45,811                  53,471                  53,372
<ALLOWANCES>                                     1,674                   3,101                   1,707
<INVENTORY>                                          0                       0                       0
<CURRENT-ASSETS>                               231,193                 246,449                 427,545
<PP&E>                                          47,942                  53,105                  52,771
<DEPRECIATION>                                  30,909                  33,452                  32,413
<TOTAL-ASSETS>                                 252,749                 270,603                 456,820
<CURRENT-LIABILITIES>                           70,225                  74,253                  99,944
<BONDS>                                            408                      31                       3
<PREFERRED-MANDATORY>                                0                       0                       0
<PREFERRED>                                          0                       0                       0
<COMMON>                                           779                     783                     840
<OTHER-SE>                                     179,270                 193,332                 354,466
<TOTAL-LIABILITY-AND-EQUITY>                   252,749                 270,603                 456,820
<SALES>                                         40,493                  84,569                 134,109
<TOTAL-REVENUES>                                60,632                 126,650                 199,798
<CGS>                                            2,502                   5,476                   8,600
<TOTAL-COSTS>                                   10,762                  22,228                  35,299
<OTHER-EXPENSES>                                39,845                  82,451                 184,571
<LOSS-PROVISION>                                     0                       0                       0   
<INTEREST-EXPENSE>                             (1,708)                 (3,639)                 (7,401)
<INCOME-PRETAX>                                 11,733                  25,610                (12,671)
<INCOME-TAX>                                     2,789                   6,156                   1,443
<INCOME-CONTINUING>                              8,944                  19,454                (14,114)
<DISCONTINUED>                                       0                       0                       0
<EXTRAORDINARY>                                      0                       0                       0
<CHANGES>                                            0                       0                       0
<NET-INCOME>                                     8,944                  19,454                (14,114)
<EPS-PRIMARY>                                     $.12                    $.25                  ($.18)
<EPS-DILUTED>                                     $.11                    $.23                  ($.18)
        

</TABLE>