WARNING: THE EDGAR SYSTEM ENCOUNTERED ERROR(S) WHILE PROCESSING THIS SCHEDULE.

  

                                                                      EXHIBIT 27

<ARTICLE>                     5
              
<MULTIPLIER>                                   1,000
       
                                                                                               
<PERIOD-TYPE>                   3-MOS                    6-MOS               9-MOS             12-MOS          YEAR
<FISCAL-YEAR-END>                DEC-31-1998             DEC-31-1998         DEC-31-1998       DEC-31-1998    DEC-31-1998 
<PERIOD-START>                   JAN-01-1998             APR-01-1998         JUL-01-1998       OCT-01-1998    JAN-01-1998
<PERIOD-END>                     MAR-31-1998             JUN-30-1998         SEP-30-1998       DEC-31-1998    DEC-31-1998
<CASH>                                 8,885                   5,407                 744               659            659 
<SECURITIES>                               0                       0                   0                 0              0
<RECEIVABLES>                         51,819                  51,969              56,427            54,314         54,314
<ALLOWANCES>                          (4,882)                 (5,112)             (5,628)           (5,702)        (5,702)          
<INVENTORY>                                0                       0                   0                 0              0    
<CURRENT-ASSETS>                      68,942                  66,599              68,628            69,789         69,789   
<PP&E>                               222,840                 235,145             255,921           256,469        256,469 
<DEPRECIATION>                       (87,563)                (91,417)            (94,801)          (97,471)       (97,471) 
<TOTAL-ASSETS>                       211,159                 216,607             242,842           241,799        241,799 
<CURRENT-LIABILITIES>                 43,577                  44,795              51,624            54,481         54,481
<BONDS>                                    0                       0                   0                 0              0 
<PREFERRED-MANDATORY>                      0                       0                   0                 0              0
<PREFERRED>                                0                       0                   0                 0              0
<COMMON>                                 831                     831                 831               831            831
<OTHER-SE>                            86,583                  90,153              93,575            95,806         95,806
<TOTAL-LIABILITY-AND-EQUITY>         211,159                 216,607             242,842           241,799        241,799 
<SALES>                               88,694                  95,640              99,266            99,478        383,078 
<TOTAL-REVENUES>                      88,694                  95,640              99,266            99,478        383,078 
<CGS>                                      0                       0                   0                 0              0 
<TOTAL-COSTS>                         84,605                  88,862              92,531            94,503        360,501 
<OTHER-EXPENSES>                          91                      85                  87                48            311
<LOSS-PROVISION>                           0                       0                   0                 0              0
<INTEREST-EXPENSE>                       913                     960               1,129             1,329          4,331 
<INCOME-PRETAX>                        3,085                   5,733               5,519             3,598         17,935 
<INCOME-TAX>                           1,172                   2,179               2,097             1,367          6,815
<INCOME-CONTINUING>                    1,913                   3,554               3,422             2,231         11,120 
<DISCONTINUED>                             0                       0                   0                 0              0 
<EXTRAORDINARY>                            0                       0                   0                 0              0
<CHANGES>                                  0                       0                   0                 0              0
<NET-INCOME>                           1,913                   3,554               3,422             2,231         11,120 
<EPS-PRIMARY>                           0.23                    0.43                0.41              0.27           1.34<F1>
<EPS-DILUTED>                           0.23                    0.43                0.41              0.27           1.34
        

<FN>
EPS-BASIC
</FN>