<TABLE> <S> <C>

<PAGE>

<ARTICLE> 7

<S>                             <C>                     <C>
<PERIOD-TYPE>                   3-MOS                   9-MOS
<FISCAL-YEAR-END>                          DEC-31-1999             DEC-31-1999
<PERIOD-START>                             JUL-01-1999             JAN-01-1999
<PERIOD-END>                               SEP-30-1999             SEP-30-1999
<DEBT-HELD-FOR-SALE>                         1,313,815               1,313,815
<DEBT-CARRYING-VALUE>                                0                       0
<DEBT-MARKET-VALUE>                                  0                       0
<EQUITIES>                                      96,035                  96,035
<MORTGAGE>                                           0                       0
<REAL-ESTATE>                                        0                       0
<TOTAL-INVEST>                               1,409,850               1,409,850
<CASH>                                          87,486                  87,486
<RECOVER-REINSURE>                              53,650                  53,650
<DEFERRED-ACQUISITION>                         133,386                 133,386
<TOTAL-ASSETS>                               2,607,742               2,607,742
<POLICY-LOSSES>                              1,216,494               1,216,494
<UNEARNED-PREMIUMS>                            537,235                 537,235
<POLICY-OTHER>                                       0                       0
<POLICY-HOLDER-FUNDS>                                0                       0
<NOTES-PAYABLE>                                175,000                 175,000
<PREFERRED-MANDATORY>                                0                       0
<PREFERRED>                                          0                       0
<COMMON>                                       151,636                 151,636
<OTHER-SE>                                     374,378                 374,378
<TOTAL-LIABILITY-AND-EQUITY>                 2,607,742               2,607,742
<PREMIUMS>                                     162,973                 459,371
<INVESTMENT-INCOME>                             23,289                  69,745
<INVESTMENT-GAINS>                             (1,654)                  29,626
<OTHER-INCOME>                                   3,084                  11,985
<BENEFITS>                                     112,063                 313,934
<UNDERWRITING-AMORTIZATION>                     55,597                 170,665
<UNDERWRITING-OTHER>                             4,444                  16,966
<INCOME-PRETAX>                                 10,152                  43,912
<INCOME-TAX>                                   (1,816)                 (2,355)
<INCOME-CONTINUING>                             11,968                  46,267
<DISCONTINUED>                                       0                       0
<EXTRAORDINARY>                                      0                       0
<CHANGES>                                            0                       0
<NET-INCOME>                                    11,968                  46,267
<EPS-BASIC>                                       0.47                    1.83
<EPS-DILUTED>                                     0.45                    1.77
<RESERVE-OPEN>                                 960,036                 982,904
<PROVISION-CURRENT>                            105,611                 329,311
<PROVISION-PRIOR>                                6,453                (15,376)
<PAYMENTS-CURRENT>                              20,697                 43,235
<PAYMENTS-PRIOR>                                85,478                 83,492
<RESERVE-CLOSE>                                967,911                 967,911
<CUMULATIVE-DEFICIENCY>                              0                       0


</TABLE>