<ARTICLE> 5
<MULTIPLIER> 1000

                                                  
<PERIOD-TYPE>                   3-MOS                   9-MOS
<FISCAL-YEAR-END>               DEC-31-1999                DEC-31-1999
<PERIOD-END>                    SEP-30-1999                SEP-30-1999
<CASH>                                         132,252                 132,252
<SECURITIES>                                   430,561                 430,561
<RECEIVABLES>                                  121,545                 121,545
<ALLOWANCES>                                     2,640                   2,640
<INVENTORY>                                     14,883                  14,883
<CURRENT-ASSETS>                               746,416                 746,416
<PP&E>                                         336,137                 336,137
<DEPRECIATION>                                 175,604                 175,604
<TOTAL-ASSETS>                               1,031,639               1,031,639
<CURRENT-LIABILITIES>                          261,391                 261,391
<BONDS>                                              0                       0
<PREFERRED-MANDATORY>                                0                       0
<PREFERRED>                                          0                       0
<COMMON>                                        71,461                  71,461
<OTHER-SE>                                     600,196                 600,196
<TOTAL-LIABILITY-AND-EQUITY>                 1,031,639               1,031,639
<SALES>                                        231,253                 621,805
<TOTAL-REVENUES>                               231,253                 621,805
<CGS>                                          162,838                 438,296
<TOTAL-COSTS>                                  178,826                 519,229
<OTHER-EXPENSES>                                     0                       0
<LOSS-PROVISION>                                   860                   2,942
<INTEREST-EXPENSE>                               1,484                   8,628
<INCOME-PRETAX>                                 58,014                 111,822
<INCOME-TAX>                                    20,442                  44,355
<INCOME-CONTINUING>                             37,572                  67,467
<DISCONTINUED>                                       0                       0
<EXTRAORDINARY>                                      0                       0
<CHANGES>                                            0                       0
<NET-INCOME>                                    37,572                  67,467
<EPS-BASIC>                                       0.18                    0.33
<EPS-DILUTED>                                     0.17                    0.32