<TABLE> <S> <C>

<PAGE>
<ARTICLE> 9
<LEGEND>
THIS SCHEDULE CONTAINS SUMMARY FINANCIAL INFORMATION EXTRACTED FROM HE
FINANCIAL STATEMENTS OF CITIZENS NATIONAL BANK OF TEXAS AT DECEMBER 31, 1997,
AND THE YEAR THEN ENDED AND AT MARCH 31, 1998, AND FOR THE THREE MONTHS ENDED
AND IS QUALIFIED IN ITS ENTIRETY BY REFERENCE TO SUCH FINANCIAL STATEMENTS
</LEGEND>
<MULTIPLIER> 1,000
       
<S>                             <C>                     <C>
<PERIOD-TYPE>                   12-MOS                   3-MOS
<FISCAL-YEAR-END>                          DEC-31-1997             DEC-31-1998
<PERIOD-START>                             JAN-01-1997             JAN-01-1998
<PERIOD-END>                               DEC-31-1997             MAR-31-1998
<CASH>                                          12,099                  11,273
<INT-BEARING-DEPOSITS>                         206,309                 215,895
<FED-FUNDS-SOLD>                                     0                       0
<TRADING-ASSETS>                                     0                       0
<INVESTMENTS-HELD-FOR-SALE>                     93,036                  96,369
<INVESTMENTS-CARRYING>                          76,795                 101,811
<INVESTMENTS-MARKET>                            77,569                 102,018
<LOANS>                                        102,875                 105,980
<ALLOWANCE>                                      1,009                   1,015
<TOTAL-ASSETS>                                 295,606                 322,775
<DEPOSITS>                                     260,907                 273,238
<SHORT-TERM>                                         0                   5,300
<LIABILITIES-OTHER>                              3,051                   2,319
<LONG-TERM>                                          0                  10,000
<PREFERRED-MANDATORY>                                0                       0
<PREFERRED>                                          0                       0
<COMMON>                                        10,242                  10,242
<OTHER-SE>                                      21,405                  21,656
<TOTAL-LIABILITIES-AND-EQUITY>                 295,606                 322,775
<INTEREST-LOAN>                                  9,572                   2,606
<INTEREST-INVEST>                               10,369                   2,825
<INTEREST-OTHER>                                     0                       0
<INTEREST-TOTAL>                                19,941                   5,431
<INTEREST-DEPOSIT>                               8,821                   2,404
<INTEREST-EXPENSE>                               9,075                   2,404
<INTEREST-INCOME-NET>                           10,866                   3,027
<LOAN-LOSSES>                                      877                     165
<SECURITIES-GAINS>                                 263                      51
<EXPENSE-OTHER>                                  7,644                   2,147
<INCOME-PRETAX>                                  4,852                   1,335
<INCOME-PRE-EXTRAORDINARY>                       4,852                   1,335
<EXTRAORDINARY>                                      0                       0
<CHANGES>                                            0                       0
<NET-INCOME>                                     3,698                   1,010
<EPS-PRIMARY>                                     0.89                    0.20
<EPS-DILUTED>                                     0.88                    0.20
<YIELD-ACTUAL>                                    7.74                    7.70
<LOANS-NON>                                        279                     220
<LOANS-PAST>                                     1,016                     526
<LOANS-TROUBLED>                                    54                      52
<LOANS-PROBLEM>                                  1,349                     798
<ALLOWANCE-OPEN>                                   687                   1,009
<CHARGE-OFFS>                                      636                     185
<RECOVERIES>                                        81                      26
<ALLOWANCE-CLOSE>                                1,009                   1,015
<ALLOWANCE-DOMESTIC>                             1,009                   1,015
<ALLOWANCE-FOREIGN>                                  0                       0
<ALLOWANCE-UNALLOCATED>                              0                       0
        

</TABLE>