<ARTICLE> 5
<MULTIPLIER> 1,000
       
                                                             
<PERIOD-TYPE>                              12-MOS                  
<FISCAL-YEAR-END>                          DEC-31-1997  
<PERIOD-START>                             JAN-01-1997  
<PERIOD-END>                               DEC-31-1997  
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<PP&E>                                       1,013,803  
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<CGS>                                          295,511  
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<NET-INCOME>                                    29,261  
<EPS-PRIMARY>                                      .93  
<EPS-DILUTED>                                      .92