<TABLE> <S> <C>

<ARTICLE> 5
<RESTATED> 
       
<S>                             <C>                     <C>                    <C>                   <C>
<PERIOD-TYPE>                   3-MOS                   6-MOS                  9-MOS                 12-MOS
<FISCAL-YEAR-END>                         DEC-31-1997          DEC-31-1997            DEC-31-1997            DEC-31-1997
<PERIOD-START>                            JAN-01-1997          JAN-01-1997            JAN-01-1997            JAN-01-1997
<PERIOD-END>                              MAR-31-1997          JUN-30-1997            SEP-30-1997            DEC-31-1997
<CASH>                                         18,586               12,787                 11,943                 10,982
<SECURITIES>                                      984                    0                      0                      0
<RECEIVABLES>                                  27,286               30,683                 35,057                 35,477
<ALLOWANCES>                                  (1,871)              (1,740)                (2,516)                (3,356)
<INVENTORY>                                     1,190                1,473                  1,493                  1,675
<CURRENT-ASSETS>                               49,486               46,509                 50,628                 50,644
<PP&E>                                         31,625               33,927                 39,440                 41,521
<DEPRECIATION>                               (15,119)             (16,554)               (19,532)               (19,354)
<TOTAL-ASSETS>                                117,390              118,646                128,239                139,106
<CURRENT-LIABILITIES>                          23,369               20,008                 22,824                 24,002
<BONDS>                                         6,468                5,617                  5,712                  6,796
<PREFERRED-MANDATORY>                               0                    0                      0                      0
<PREFERRED>                                         0                    0                      0                      0
<COMMON>                                          115                  117                    119                    125
<OTHER-SE>                                     88,326               93,073                 99,800                107,439
<TOTAL-LIABILITY-AND-EQUITY>                  117,390              118,646                128,239                139,106
<SALES>                                         1,765                3,590                  5,878                  7,845
<TOTAL-REVENUES>                               39,417               80,484                127,086                177,272
<CGS>                                           1,351                2,773                  4,527                  5,949
<TOTAL-COSTS>                                  33,373               68,013                108,654                151,161
<OTHER-EXPENSES>                                (276)                (460)                  (593)                  (743)
<LOSS-PROVISION>                                   24                  142                    438                    601
<INTEREST-EXPENSE>                                211                  417                    590                  1,919
<INCOME-PRETAX>                                 4,900               10,016                 14,565                 19,370
<INCOME-TAX>                                    1,569                3,355                  4,869                  6,507
<INCOME-CONTINUING>                             3,331                6,661                  9,696                 12,863
<DISCONTINUED>                                      0                    0                      0                      0
<EXTRAORDINARY>                                     0                    0                      0                      0
<CHANGES>                                           0                    0                      0                      0
<NET-INCOME>                                    3,331                6,661                  9,696                 12,863
<EPS-PRIMARY>                                    0.28                 0.57                   0.82                   1.07
<EPS-DILUTED>                                    0.28                 0.56                   0.80                   1.05
        

</TABLE>