<ARTICLE> 5

                                                  
<PERIOD-TYPE>                   6-MOS                   6-MOS
<FISCAL-YEAR-END>                          DEC-31-2000             DEC-31-1999
<PERIOD-END>                               JUN-30-2000             JUN-30-1999
<CASH>                                       4,953,435              11,625,107
<SECURITIES>                                69,264,966              37,110,776
<RECEIVABLES>                               17,670,771              17,642,029
<ALLOWANCES>                                         0                       0
<INVENTORY>                                  3,302,509               2,269,821
<CURRENT-ASSETS>                            27,295,981              34,364,617
<PP&E>                                     248,714,261             206,159,583
<DEPRECIATION>                             112,059,627             100,260,239
<TOTAL-ASSETS>                             273,097,704             212,596,619
<CURRENT-LIABILITIES>                       23,220,488              25,644,073
<BONDS>                                     33,000,000              20,000,000
<PREFERRED-MANDATORY>                          112,500                 125,000
<PREFERRED>                                    397,000                 400,400
<COMMON>                                    42,270,297              39,458,340
<OTHER-SE>                                 132,675,784              96,881,343
<TOTAL-LIABILITY-AND-EQUITY>               273,097,704             212,596,619
<SALES>                                              0                       0
<TOTAL-REVENUES>                            56,810,155              51,433,818
<CGS>                                                0                       0
<TOTAL-COSTS>                               47,305,854              40,550,648
<OTHER-EXPENSES>                           (8,893,488)            (12,401,892)
<LOSS-PROVISION>                                     0                       0
<INTEREST-EXPENSE>                           1,405,175               1,335,150
<INCOME-PRETAX>                             16,992,614              21,949,912
<INCOME-TAX>                                 6,822,943               8,937,063
<INCOME-CONTINUING>                         10,169,671              13,012,849
<DISCONTINUED>                                       0                       0
<EXTRAORDINARY>                                      0                       0
<CHANGES>                                            0                       0
<NET-INCOME>                                10,169,671              13,012,849
<EPS-BASIC>                                       0.54                    0.70
<EPS-DILUTED>                                     0.54                    0.69