<TABLE> <S> <C>

<ARTICLE> 5
       
<S>                             <C>               <C>               <C>               <C>         
<PERIOD-TYPE>                   3-MOS             3-MOS             3-MOS             3-MOS      
<FISCAL-YEAR-END>               DEC-31-1997       DEC-31-1997       DEC-31-1997       DEC-31-1997 
<PERIOD-START>                  JAN-01-1997       APR-01-1997       JUL-01-1997       OCT-01-1997 
<PERIOD-END>                    MAR-31-1997       JUN-30-1997       SEP-30-1997       DEC-31-1997 
<CASH>                            144,116           145,041           155,363           123,494   
<SECURITIES>                      133,118           129,822           113,853           123,882   
<RECEIVABLES>                      87,805           103,114           106,705           125,284   
<ALLOWANCES>                            0                 0                 0                 0   
<INVENTORY>                             0                 0                 0                 0   
<CURRENT-ASSETS>                  398,640           410,502           410,269           430,272   
<PP&E>                             68,934            76,695            83,993            89,551   
<DEPRECIATION>                   (37,404)          (39,225)          (43,492)          (60,981)   
<TOTAL-ASSETS>                    505,334           533,637           564,192           601,931   
<CURRENT-LIABILITIES>             129,419           116,583           125,620           228,986   
<BONDS>                                 0                 0                 0                 0   
<PREFERRED-MANDATORY>                 675               689               686               699   
<PREFERRED>                             0                 0                 0                 0   
<COMMON>                                0                 0                 0                 0   
<OTHER-SE>                        366,959           407,021           426,709           359,060   
<TOTAL-LIABILITY-AND-EQUITY>      505,334           533,837           564,192           601,931   
<SALES>                           141,362           144,594           152,932           173,305   
<TOTAL-REVENUES>                  141,362           144,594           152,932           173,305   
<CGS>                              27,582            22,108            23,555            34,971   
<TOTAL-COSTS>                      85,595            78,411           105,409           216,341   
<OTHER-EXPENSES>                        0                 0                 0                 0   
<LOSS-PROVISION>                        0                 0                 0                 0   
<INTEREST-EXPENSE>                      0                 0                 0                 0   
<INCOME-PRETAX>                    31,082            48,671            27,569          (74,358)   
<INCOME-TAX>                       17,811            18,023            18,948             6,538   
<INCOME-CONTINUING>                13,271            30,648             8,621          (80,896)   
<DISCONTINUED>                          0                 0                 0                 0   
<EXTRAORDINARY>                         0                 0                 0                 0   
<CHANGES>                               0                 0                 0                 0   
<NET-INCOME>                       13,271            30,648             8,621          (80,896)   
<EPS-PRIMARY>                        0.20              0.45              0.12            (1.16)   
<EPS-DILUTED>                        0.18              0.42              0.12            (1.16)   
        

</TABLE>