<ARTICLE>                    5
<LEGEND>
THIS SCHEDULE CONTAINS SUMMARY FINANCIAL INFORMATION EXTRACTED FROM THE
CONSOLIDATED BALANCE SHEET AND THE CONSOLIDATED STATEMENT OF OPERATIONS AND IS
QUALIFIED IN ITS ENTIRETY BY REFERENCE TO SUCH FINANCIAL STATEMENTS.
</LEGEND>
<MULTIPLIER>                    1,000
       
                             
<PERIOD-TYPE>                   9-MOS
<FISCAL-YEAR-END>                        DEC-31-1998
<PERIOD-END>                             SEP-30-1998
<CASH>                                        16,714
<SECURITIES>                                  34,192
<RECEIVABLES>                                 36,003
<ALLOWANCES>                                       0
<INVENTORY>                                    6,034
<CURRENT-ASSETS>                              96,099
<PP&E>                                        26,269
<DEPRECIATION>                                18,126
<TOTAL-ASSETS>                               114,268
<CURRENT-LIABILITIES>                         11,299
<BONDS>                                            0
<PREFERRED-MANDATORY>                              0
<PREFERRED>                                        0
<COMMON>                                         485
<OTHER-SE>                                    98,483
<TOTAL-LIABILITY-AND-EQUITY>                 114,268
<SALES>                                       50,554
<TOTAL-REVENUES>                              55,653
<CGS>                                          7,733
<TOTAL-COSTS>                                 37,175
<OTHER-EXPENSES>                                   0
<LOSS-PROVISION>                                   0
<INTEREST-EXPENSE>                                65
<INCOME-PRETAX>                               18,478
<INCOME-TAX>                                   5,543
<INCOME-CONTINUING>                           12,935
<DISCONTINUED>                                     0
<EXTRAORDINARY>                                    0
<CHANGES>                                          0
<NET-INCOME>                                  12,935
<EPS-PRIMARY>                                   0.27
<EPS-DILUTED>                                   0.26