<TABLE> <S> <C>
<PAGE>
<ARTICLE> 5
<LEGEND>
THIS SCHEDULE CONTAINS SUMMARY FINANCIAL INFORMATION EXTRACTED FROM THE
COMPANY'S FINANCIAL STATEMENTS INCLUDED IN THIS REGISTRATION STATEMENT ON FORM
S-1, AND IS QUALIFIED IN ITS ENTIRETY BY REFERENCE TO SUCH FINANCIAL STATEMENTS.
</LEGEND>
<S> <C>
<PERIOD-TYPE> 6-MOS
<FISCAL-YEAR-END> DEC-31-1999
<PERIOD-END> JUN-30-2000
<CASH> 6,107,000
<SECURITIES> 29,775,000
<RECEIVABLES> 74,517,000
<ALLOWANCES> 3,451,000
<INVENTORY> 0
<CURRENT-ASSETS> 186,904,000
<PP&E> 292,921,000
<DEPRECIATION> 167,720,000
<TOTAL-ASSETS> 554,018,000
<CURRENT-LIABILITIES> 196,482,000
<BONDS> 0
0
0
<COMMON> 870,000
<OTHER-SE> 253,955,000
<TOTAL-LIABILITY-AND-EQUITY> 554,018,000
<SALES> 288,970,000
<TOTAL-REVENUES> 288,970,000
<CGS> 249,906,000
<TOTAL-COSTS> 249,906,000
<OTHER-EXPENSES> 791,000
<LOSS-PROVISION> 0
<INTEREST-EXPENSE> 3,203,000
<INCOME-PRETAX> 35,070,000
<INCOME-TAX> 14,853,000
<INCOME-CONTINUING> 39,064,000
<DISCONTINUED> 0
<EXTRAORDINARY> 0
<CHANGES> 0
<NET-INCOME> 20,217,000
<EPS-BASIC> .23
<EPS-DILUTED> .23
</TABLE>