<ARTICLE> 5
<LEGEND>
THIS SCHEDULE CONTAINS SUMMARY FINANCIAL INFORMATION EXTRACTED FROM CONDENSED
CONSOLIDATED BALANCE SHEETS AND STATEMENTS OF EARNINGS AND IS QUALIFIED IN ITS
ENTIRETY BY REFERENCE TO SUCH FINANCIAL STATEMENTS.
</LEGEND>
<MULTIPLIER> 1,000

                             
<PERIOD-TYPE>                   6-MOS
<FISCAL-YEAR-END>                          DEC-31-1999
<PERIOD-END>                               JUN-30-1999
<CASH>                                             882
<SECURITIES>                                    17,378
<RECEIVABLES>                                   67,707
<ALLOWANCES>                                       637
<INVENTORY>                                     13,323
<CURRENT-ASSETS>                               106,134
<PP&E>                                         474,488
<DEPRECIATION>                                 221,739
<TOTAL-ASSETS>                                 379,470
<CURRENT-LIABILITIES>                           70,373
<BONDS>                                        122,969
<PREFERRED-MANDATORY>                                0
<PREFERRED>                                          0
<COMMON>                                         3,091
<OTHER-SE>                                     136,267
<TOTAL-LIABILITY-AND-EQUITY>                   379,470
<SALES>                                         30,043
<TOTAL-REVENUES>                               162,917
<CGS>                                           23,301
<TOTAL-COSTS>                                  107,095
<OTHER-EXPENSES>                                35,098
<LOSS-PROVISION>                                  (90)
<INTEREST-EXPENSE>                               5,114
<INCOME-PRETAX>                                 17,100
<INCOME-TAX>                                     6,497
<INCOME-CONTINUING>                             10,603
<DISCONTINUED>                                       0
<EXTRAORDINARY>                                      0
<CHANGES>                                            0
<NET-INCOME>                                    10,603
<EPS-BASIC>                                        .52
<EPS-DILUTED>                                      .52