<ARTICLE> 5
<MULTIPLIER> 1,000
       
                                                  
<PERIOD-TYPE>                   3-MOS                   3-MOS
<FISCAL-YEAR-END>                          DEC-31-1997             DEC-31-1996
<PERIOD-START>                             JUL-01-1997             JUL-01-1996
<PERIOD-END>                               SEP-30-1997             SEP-30-1996
<CASH>                                          29,624                   8,957
<SECURITIES>                                    80,523                  16,416
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<CURRENT-ASSETS>                               172,298                  66,864
<PP&E>                                          50,819                  33,834
<DEPRECIATION>                                  16,145                  13,402
<TOTAL-ASSETS>                                 368,616                 184,324
<CURRENT-LIABILITIES>                           39,376                  27,895
<BONDS>                                              0                       0
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<PREFERRED>                                          0                       0
<COMMON>                                           289                     228
<OTHER-SE>                                     326,293                 149,550
<TOTAL-LIABILITY-AND-EQUITY>                   368,616                 184,324
<SALES>                                              0                       0
<TOTAL-REVENUES>                                58,464                  41,482
<CGS>                                                0                       0
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<INTEREST-EXPENSE>                                  13                     198
<INCOME-PRETAX>                                 11,580                   7,239
<INCOME-TAX>                                     4,053                   2,897
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<NET-INCOME>                                     7,527                   4,342
<EPS-PRIMARY>                                     0.27                    0.19
<EPS-DILUTED>                                     0.26                    0.17