<TABLE> <S> <C>

<PAGE>
<ARTICLE> 5
<LEGEND>
THIS SCHEDULE CONTAINS SUMMARY FINANCIAL INFORMATION EXTRACTED FROM THE
BALANCE SHEETS FOR DECEMBER 31, SEPTEMBER 30 AND JUNE 30, 1996 AND THE
STATEMENTS OF OPERATIONS FOR THE YEAR ENDED DECEMBER 30, THE NINE MONTHS
ENDED SEPTEMBER 30 AND THE SIX MONTHS ENDED JUNE 30, 1996 AND IS QUALIFIED
IN ITS ENTIRETY BY REFERENCE TO SUCH FINANCIAL STATEMENTS.
</LEGEND>
<RESTATED>

<S>                             <C>                     <C>                     <C>
<PERIOD-TYPE>                   YEAR                   9-MOS                   6-MOS
<FISCAL-YEAR-END>                          DEC-31-1996             DEC-31-1996             DEC-31-1996
<PERIOD-START>                             JAN-01-1996             JAN-01-1996             JAN-01-1996
<PERIOD-END>                               DEC-31-1996             SEP-30-1996             JUN-30-1996
<CASH>                                      15,796,070              22,252,710              26,291,813
<SECURITIES>                                12,968,163               4,002,594               3,965,421
<RECEIVABLES>                                9,312,277               7,220,217               6,390,052
<ALLOWANCES>                                 1,123,562                 782,149                 865,772
<INVENTORY>                                    683,408                 586,552                 548,396
<CURRENT-ASSETS>                            38,833,814              34,418,340              37,511,926
<PP&E>                                       7,656,299               5,743,254               5,201,774
<DEPRECIATION>                               2,910,637               2,612,138               2,329,681
<TOTAL-ASSETS>                              50,269,909              47,471,098              47,175,475
<CURRENT-LIABILITIES>                        3,924,220               2,183,719               2,399,558
<BONDS>                                              0                       0                       0
<PREFERRED-MANDATORY>                                0                       0                       0
<PREFERRED>                                          0                       0                       0
<COMMON>                                       101,013                 100,170                 100,165
<OTHER-SE>                                  45,585,545              44,373,677              43,706,315
<TOTAL-LIABILITY-AND-EQUITY>                50,269,909              47,471,098              47,175,475
<SALES>                                              0                       0                       0
<TOTAL-REVENUES>                            26,522,205              18,832,561              12,356,722
<CGS>                                                0                       0                       0
<TOTAL-COSTS>                                9,965,639               7,104,132               4,528,202
<OTHER-EXPENSES>                            13,888,430              10,079,476               6,680,891
<LOSS-PROVISION>                             1,294,365                 877,407                 578,157
<INTEREST-EXPENSE>                             225,531                 170,782                 109,889
<INCOME-PRETAX>                              2,363,384               1,332,911                 697,934
<INCOME-TAX>                                         0                       0                       0
<INCOME-CONTINUING>                          2,363,384               1,332,911                 697,934
<DISCONTINUED>                                       0                       0                       0
<EXTRAORDINARY>                                      0                       0                       0
<CHANGES>                                            0                       0                       0
<NET-INCOME>                                 2,363,384               1,332,911                 697,934
<EPS-PRIMARY>                                     0.27                    0.16                    0.09
<EPS-DILUTED>                                     0.24                    0.14                    0.08


</TABLE>