<ARTICLE> 5 <MULTIPLIER> 1,000 <CURRENCY> US DOLLARS <PERIOD-TYPE> 9-MOS <FISCAL-YEAR-END> DEC-31-1998 <PERIOD-START> JAN-01-1998 <PERIOD-END> SEP-30-1998 <EXCHANGE-RATE> 1 <CASH> 8,469 <SECURITIES> 0 <RECEIVABLES> 103,660 <ALLOWANCES> 2,756 <INVENTORY> 0 <CURRENT-ASSETS> 129,397 <PP&E> 97,487 <DEPRECIATION> 55,303 <TOTAL-ASSETS> 389,643 <CURRENT-LIABILITIES> 88,397 <BONDS> 0 <PREFERRED-MANDATORY> 0 <PREFERRED> 0 <COMMON> 1,465 <OTHER-SE> 142,082 <TOTAL-LIABILITY-AND-EQUITY> 389,643 <SALES> 303,139 <TOTAL-REVENUES> 303,139 <CGS> 200,823 <TOTAL-COSTS> 200,823 <OTHER-EXPENSES> 54,580 <LOSS-PROVISION> 0 <INTEREST-EXPENSE> 5,271 <INCOME-PRETAX> 42,465 <INCOME-TAX> 18,387 <INCOME-CONTINUING> 24,078 <DISCONTINUED> 0 <EXTRAORDINARY> 0 <CHANGES> 0 <NET-INCOME> 24,078 <EPS-PRIMARY> 1.65 <EPS-DILUTED> 1.60