<TABLE> <S> <C>

<PAGE>
<ARTICLE> 5
<RESTATED>
       
<S>                             <C>                     <C>                     <C>
<PERIOD-TYPE>                   3-MOS                   6-MOS                   9-MOS
<FISCAL-YEAR-END>                          DEC-31-1997             DEC-31-1997             DEC-31-1997
<PERIOD-START>                             JAN-01-1997             JAN-01-1997             JAN-01-1997
<PERIOD-END>                               MAR-31-1997             JUN-30-1997             SEP-30-1997
<CASH>                                         798,464               1,254,362               1,268,046
<SECURITIES>                                         0                       0                       0
<RECEIVABLES>                                  903,027                 117,314                 110,030
<ALLOWANCES>                                         0                       0                       0
<INVENTORY>                                          0                       0                       0
<CURRENT-ASSETS>                             4,536,196               3,715,341               3,359,930
<PP&E>                                       2,854,968               3,212,364               3,713,014
<DEPRECIATION>                                 503,710                 522,447                 555,893
<TOTAL-ASSETS>                               7,310,678               6,832,835               6,972,494
<CURRENT-LIABILITIES>                        2,948,102               1,649,092                 950,906
<BONDS>                                              0                       0                       0
<PREFERRED-MANDATORY>                                0                       0                       0
<PREFERRED>                                    760,260                 760,260                 760,260
<COMMON>                                        58,566                  58,566                  59,066
<OTHER-SE>                                   3,046,282               4,656,407               5,464,384
<TOTAL-LIABILITY-AND-EQUITY>                 7,310,678               6,832,835               6,972,494
<SALES>                                      2,837,892               5,707,316               8,608,274
<TOTAL-REVENUES>                             2,840,248               5,716,137               8,632,675
<CGS>                                                0                       0                       0
<TOTAL-COSTS>                                  928,740               1,907,042               3,022,259
<OTHER-EXPENSES>                               529,495               1,079,724               1,649,745
<LOSS-PROVISION>                                     0                       0                       0
<INTEREST-EXPENSE>                              43,338                  63,815                  72,738
<INCOME-PRETAX>                              1,338,675               2,665,556               3,887,933
<INCOME-TAX>                                   516,219               1,029,151               1,502,371
<INCOME-CONTINUING>                            822,456               1,636,405               2,385,562
<DISCONTINUED>                                       0                       0                       0
<EXTRAORDINARY>                                      0                       0                       0
<CHANGES>                                            0                       0                       0
<NET-INCOME>                                   822,456               1,636,405               2,385,562
<EPS-PRIMARY>                                     0.14<F1>                0.27<F1>                0.40<F1>
<EPS-DILUTED>                                     0.12<F2>                0.25<F2>                0.36<F2>
<FN>
<F1>EPS-Basic per SFAS No. 128
<F2>EPS-Diluted per SFAS No. 128
</FN>
        

</TABLE>