<ARTICLE> 5
<MULTIPLIER> 1,000
       
                                                     
<PERIOD-TYPE>                   YEAR                       YEAR
<FISCAL-YEAR-END>                          DEC-31-1995             DEC-31-1994
<PERIOD-START>                             JAN-01-1995             JAN-01-1994
<PERIOD-END>                               DEC-31-1995             DEC-31-1994
<CASH>                                          32,421                  74,126
<SECURITIES>                                         0                       0
<RECEIVABLES>                                   91,447                 122,258
<ALLOWANCES>                                       457                     627
<INVENTORY>                                     43,072                  28,131
<CURRENT-ASSETS>                               170,024                 226,719
<PP&E>                                         691,806                 573,499
<DEPRECIATION>                                 337,175                 290,180
<TOTAL-ASSETS>                                 568,507                 542,904
<CURRENT-LIABILITIES>                          144,711                 169,745
<BONDS>                                        200,000                 120,000
<PREFERRED-MANDATORY>                                0                       0
<PREFERRED>                                          0                       0
<COMMON>                                             0                       0
<OTHER-SE>                                     216,464                 245,735
<TOTAL-LIABILITY-AND-EQUITY>                   568,507                 542,904
<SALES>                                        739,587                 657,752
<TOTAL-REVENUES>                               739,587                 657,752
<CGS>                                          516,527                 446,216
<TOTAL-COSTS>                                  516,527                 446,216
<OTHER-EXPENSES>                                30,941                  27,697
<LOSS-PROVISION>                                     0                       0
<INTEREST-EXPENSE>                              19,066                  16,342
<INCOME-PRETAX>                                150,926                 146,405
<INCOME-TAX>                                         0                       0
<INCOME-CONTINUING>                            150,926                 146,405
<DISCONTINUED>                                       0                       0
<EXTRAORDINARY>                                (6,912)                       0
<CHANGES>                                            0                       0
<NET-INCOME>                                   144,014                 146,405
<EPS-PRIMARY>                                     3.88                    3.94
<EPS-DILUTED>                                     3.88                    3.94