<TABLE> <S> <C>
<PAGE>
<ARTICLE> 5
<S> <C> <C>
<PERIOD-TYPE> 3-MOS 6-MOS
<FISCAL-YEAR-END> DEC-31-2000 DEC-31-2000
<PERIOD-END> MAR-31-2000 JUN-30-2000
<CASH> 20,329 6,360
<SECURITIES> 31,507 47,406
<RECEIVABLES> 126,972 151,067
<ALLOWANCES> 4,210 4,524
<INVENTORY> 0 0
<CURRENT-ASSETS> 14,791 7,939
<PP&E> 187,232 222,374
<DEPRECIATION> 72,638 81,427
<TOTAL-ASSETS> 355,662 465,864
<CURRENT-LIABILITIES> 76,661 116,142
<BONDS> 0 0
0 0
0 0
<COMMON> 653 660
<OTHER-SE> 234,388 295,879
<TOTAL-LIABILITY-AND-EQUITY> 355,662 465,864
<SALES> 172,505 369,854
<TOTAL-REVENUES> 172,505 369,854
<CGS> 113,657 245,991
<TOTAL-COSTS> 155,790 335,027
<OTHER-EXPENSES> (685) (13,398)
<LOSS-PROVISION> 0 0
<INTEREST-EXPENSE> 895 2,088
<INCOME-PRETAX> 16,505 46,137
<INCOME-TAX> 6,390 17,567
<INCOME-CONTINUING> 10,115 28,570
<DISCONTINUED> 0 0
<EXTRAORDINARY> 0 0
<CHANGES> 0 0
<NET-INCOME> 10,115 28,171
<EPS-BASIC> .16 .43
<EPS-DILUTED> .14 .40
</TABLE>