<TABLE> <S> <C>

<PAGE>
<ARTICLE> 9
<LEGEND>
THIS SCHEDULE CONTAINS SUMMARY FINANCIAL INFORMATION EXTRACTED FROM UNAUDITED
FINANCIAL STATEMENTS CONTAINED IN THE COMPANY'S QUARTERLY REPORTS IN FORM 10-Q
FOR QUARTERS ENDED MARCH 31, 1998, JUNE 30, 1998 AND SEPTEMBER 30, 1998 AND IS
QUALIFIED IN ITS ENTIRETY BY REFERENCE TO SUCH FINANCIAL STATEMENTS.
</LEGEND>
<MULTIPLIER> 1,000
       
<S>                             <C>                     <C>                     <C>
<PERIOD-TYPE>                   3-MOS                   6-MOS                   9-MOS
<FISCAL-YEAR-END>                          DEC-31-1998             DEC-31-1998             DEC-31-1998
<PERIOD-START>                             JAN-01-1998             JAN-01-1998             JAN-01-1998
<PERIOD-END>                               MAR-31-1998             JUN-30-1998             SEP-30-1998
<CASH>                                         207,030                 251,394                 216,826
<INT-BEARING-DEPOSITS>                          13,601                  14,032                   7,482
<FED-FUNDS-SOLD>                               106,700                  52,870                  40,990
<TRADING-ASSETS>                                     0                       0                       0
<INVESTMENTS-HELD-FOR-SALE>                  1,847,994               1,965,743               1,940,993
<INVESTMENTS-CARRYING>                         105,177                  88,585                  69,399
<INVESTMENTS-MARKET>                           105,304                  88,532                  69,399
<LOANS>                                      3,102,074               3,203,549               3,387,246
<ALLOWANCE>                                     39,997                  42,268                  45,567
<TOTAL-ASSETS>                               5,775,193               5,896,870               5,981,149
<DEPOSITS>                                   4,807,215               4,818,511               4,829,161
<SHORT-TERM>                                   184,700                 384,934                 319,912
<LIABILITIES-OTHER>                            139,246                  49,840                 176,082
<LONG-TERM>                                    127,175                 127,832                 119,280
<PREFERRED-MANDATORY>                          120,000                 120,000                 120,000
<PREFERRED>                                          0                       0                       0
<COMMON>                                           474                     474                     477
<OTHER-SE>                                     396,383                 395,279                 416,237
<TOTAL-LIABILITIES-AND-EQUITY>               5,775,193               5,896,870               5,981,149
<INTEREST-LOAN>                                 75,500                 155,023                 240,241
<INTEREST-INVEST>                               27,471                  58,721                  90,603
<INTEREST-OTHER>                                 1,171                   2,403                   3,307
<INTEREST-TOTAL>                               104,142                 216,147                 334,151
<INTEREST-DEPOSIT>                              39,710                  80,722                 121,955
<INTEREST-EXPENSE>                              44,010                  91,536                 141,959
<INTEREST-INCOME-NET>                           60,132                 124,611                 192,192
<LOAN-LOSSES>                                    1,752                   5,956                  10,782
<SECURITIES-GAINS>                                 481                     985                   1,339
<EXPENSE-OTHER>                                 49,528                 111,571                 168,848
<INCOME-PRETAX>                                 23,044                  37,299                  58,643
<INCOME-PRE-EXTRAORDINARY>                      16,767                  27,050                  40,444
<EXTRAORDINARY>                                   (68)                 (3,908)                 (3,908)
<CHANGES>                                            0                       0                       0
<NET-INCOME>                                    16,699                  23,142                  36,536
<EPS-PRIMARY>                                      .35                     .49                     .77
<EPS-DILUTED>                                      .35                     .48                     .76
<YIELD-ACTUAL>                                       0                       0                       0
<LOANS-NON>                                     12,026                  10,879                  17,848
<LOANS-PAST>                                     5,961                   3,730                   2,863
<LOANS-TROUBLED>                                   123                     105                     180
<LOANS-PROBLEM>                                      0                       0                       0
<ALLOWANCE-OPEN>                                40,045                  40,045                  40,045
<CHARGE-OFFS>                                    2,726                   5,522                   9,844
<RECOVERIES>                                       926                   1,789                   2,626
<ALLOWANCE-CLOSE>                               39,997                  42,268                  45,567
<ALLOWANCE-DOMESTIC>                                 0                       0                       0
<ALLOWANCE-FOREIGN>                                  0                       0                       0
<ALLOWANCE-UNALLOCATED>                              0                       0                       0
        

</TABLE>