<ARTICLE> 5

                                                  
<PERIOD-TYPE>                   9-MOS                   9-MOS
<FISCAL-YEAR-END>                          DEC-31-1999             DEC-31-1998
<PERIOD-END>                               SEP-30-1999             SEP-30-1998
<CASH>                                       6,957,672                 261,765
<SECURITIES>                                32,868,158                 149,085
<RECEIVABLES>                               18,536,528              15,133,282
<ALLOWANCES>                                   107,500                 108,024
<INVENTORY>                                  2,666,858               2,611,222
<CURRENT-ASSETS>                            25,349,607              20,111,215
<PP&E>                                     213,503,249             191,304,203
<DEPRECIATION>                             103,463,342              92,238,924
<TOTAL-ASSETS>                             209,459,250             191,599,063
<CURRENT-LIABILITIES>                       20,391,286              21,426,365
<BONDS>                                     20,000,000              19,118,137
<PREFERRED-MANDATORY>                          125,000                 137,500
<PREFERRED>                                    398,000                 408,100
<COMMON>                                    38,206,596              37,715,002
<OTHER-SE>                                 101,270,682              86,417,256
<TOTAL-LIABILITY-AND-EQUITY>               209,459,250             191,599,063
<SALES>                                              0                       0
<TOTAL-REVENUES>                            78,028,257              67,184,388
<CGS>                                                0                       0
<TOTAL-COSTS>                               61,293,929              50,422,582
<OTHER-EXPENSES>                           (15,644,270)               (395,157)
<LOSS-PROVISION>                                     0                       0
<INTEREST-EXPENSE>                           1,928,610                 776,650
<INCOME-PRETAX>                             30,449,988              16,380,313
<INCOME-TAX>                                12,422,328               6,844,790
<INCOME-CONTINUING>                         18,027,660               9,535,523
<DISCONTINUED>                                       0                       0
<EXTRAORDINARY>                                      0                       0
<CHANGES>                                            0                       0
<NET-INCOME>                                18,027,660               9,535,523
<EPS-BASIC>                                       1.93                    1.03
<EPS-DILUTED>                                     1.92                    1.03