<TABLE> <S> <C>

<PAGE>
<ARTICLE> 9
<MULTIPLIER>  1,000
       
<S>                             <C>                     <C>
<PERIOD-TYPE>                   3-MOS                   3-MOS
<FISCAL-YEAR-END>                          DEC-31-1998             DEC-31-1997
<PERIOD-START>                             JAN-01-1998             JAN-01-1997
<PERIOD-END>                               MAR-31-1998             MAR-31-1997
<CASH>                                         216,050                 183,451
<INT-BEARING-DEPOSITS>                          17,704                  18,304
<FED-FUNDS-SOLD>                                54,923                   4,477
<TRADING-ASSETS>                                52,049                  45,411
<INVESTMENTS-HELD-FOR-SALE>                          0                 724,847
<INVESTMENTS-CARRYING>                               0                 886,277
<INVESTMENTS-MARKET>                                 0                 870,244
<LOANS>                                      2,719,212               2,431,322
<ALLOWANCE>                                     44,643                  36,739
<TOTAL-ASSETS>                               4,992,478               4,429,162
<DEPOSITS>                                   3,509,202               2,966,508
<SHORT-TERM>                                   467,832                 610,389
<LIABILITIES-OTHER>                             91,378                  88,292
<LONG-TERM>                                    494,859                 391,977
<PREFERRED-MANDATORY>                                0                       0
<PREFERRED>                                          0                       0
<COMMON>                                       379,320                 322,121
<OTHER-SE>                                           0                       0
<TOTAL-LIABILITIES-AND-EQUITY>               4,992,478               4,429,162
<INTEREST-LOAN>                                 59,976                  53,015
<INTEREST-INVEST>                               26,811                  25,595
<INTEREST-OTHER>                                 1,440                     727
<INTEREST-TOTAL>                                88,227                  79,337
<INTEREST-DEPOSIT>                              32,813                  29,445
<INTEREST-EXPENSE>                              43,956                  41,433
<INTEREST-INCOME-NET>                           44,271                  37,904
<LOAN-LOSSES>                                      867                   3,454
<SECURITIES-GAINS>                                   2                      (1)
<EXPENSE-OTHER>                                 34,141                  20,001
<INCOME-PRETAX>                                 30,269                  23,044
<INCOME-PRE-EXTRAORDINARY>                      30,269                  23,044
<EXTRAORDINARY>                                      0                       0
<CHANGES>                                            0                       0
<NET-INCOME>                                    20,015                  15,115
<EPS-PRIMARY>                                      .20                     .16
<EPS-DILUTED>                                      .19                     .15
<YIELD-ACTUAL>                                    4.21                    3.98
<LOANS-NON>                                          0                       0
<LOANS-PAST>                                     4,602                   4,430
<LOANS-TROUBLED>                                     0                       0
<LOANS-PROBLEM>                                      0                       0
<ALLOWANCE-OPEN>                                43,297                  35,514
<CHARGE-OFFS>                                    2,525                   3,339
<RECOVERIES>                                     1,763                     785
<ALLOWANCE-CLOSE>                               44,643                  36,739
<ALLOWANCE-DOMESTIC>                            44,643                  36,739
<ALLOWANCE-FOREIGN>                                  0                       0
<ALLOWANCE-UNALLOCATED>                              0                       0
        

</TABLE>