<TABLE> <S> <C>

<PAGE>
<ARTICLE> 7
<MULTIPLIER> 1,000
       
<S>                             <C>                     <C>
<PERIOD-TYPE>                   3-MOS                   6-MOS
<FISCAL-YEAR-END>                          DEC-31-1998             DEC-31-1998
<PERIOD-START>                             APR-01-1998             JAN-01-1998
<PERIOD-END>                               JUN-30-1998             JUN-30-1998
<DEBT-HELD-FOR-SALE>                         1,318,314               1,318,314
<DEBT-CARRYING-VALUE>                                0                       0
<DEBT-MARKET-VALUE>                                  0                       0
<EQUITIES>                                      87,475                  87,475
<MORTGAGE>                                           0                       0
<REAL-ESTATE>                                        0                       0
<TOTAL-INVEST>                               1,405,789               1,405,789
<CASH>                                          78,057                  78,057
<RECOVER-REINSURE>                              49,178                  49,178
<DEFERRED-ACQUISITION>                         125,207                 125,207
<TOTAL-ASSETS>                               2,428,621               2,428,621
<POLICY-LOSSES>                              1,131,613               1,131,613
<UNEARNED-PREMIUMS>                            450,217                 450,217
<POLICY-OTHER>                                       0                       0
<POLICY-HOLDER-FUNDS>                                0                       0
<NOTES-PAYABLE>                                175,000                 175,000
<PREFERRED-MANDATORY>                                0                       0
<PREFERRED>                                          0                       0
<COMMON>                                       150,602                 150,602
<OTHER-SE>                                     366,906                 366,906
<TOTAL-LIABILITY-AND-EQUITY>                 2,428,621               2,428,621
<PREMIUMS>                                     114,708                 249,292
<INVESTMENT-INCOME>                             23,681                  46,263
<INVESTMENT-GAINS>                               3,170                  14,558
<OTHER-INCOME>                                   7,427                  10,790
<BENEFITS>                                      66,914                 162,122
<UNDERWRITING-AMORTIZATION>                     40,742                  75,165
<UNDERWRITING-OTHER>                             4,842                   9,126
<INCOME-PRETAX>                                 25,253                  55,305
<INCOME-TAX>                                     4,653                  10,282
<INCOME-CONTINUING>                             20,599                  45,023
<DISCONTINUED>                                       0                       0
<EXTRAORDINARY>                                 11,641                  11,641
<CHANGES>                                            0                       0
<NET-INCOME>                                     8,959                  33,382
<EPS-PRIMARY>                                     0.35                    1.31
<EPS-DILUTED>                                     0.34                    1.28
<RESERVE-OPEN>                                 954,509                 910,996
<PROVISION-CURRENT>                             72,314                 169,722
<PROVISION-PRIOR>                              (5,400)                 (7,600)
<PAYMENTS-CURRENT>                              23,597                  25,000
<PAYMENTS-PRIOR>                                87,838                 138,130
<RESERVE-CLOSE>                                909,988                 909,988
<CUMULATIVE-DEFICIENCY>                              0                       0
<FN>
<F1>FOREIGN EXCHANGE MOVEMENT DURING THE YEAR HAS BEEN ALLOCATED TO PRIOR YEAR PAID
CLAIMS.
</FN>
        

</TABLE>