<TABLE> <S> <C>

<PAGE>
<ARTICLE> 9
<LEGEND>
THIS SCHEDULE CONTAINS SUMMARY FINANCIAL INFORMATION EXTRACTED FROM THE MAHONING
NATIONAL BANCORP, INC., CONSOLIDATED STATEMENT OF CONDITION AT JUNE 30, 1998 AND
THE CONSOLIDATED STATEMENT OF INCOME FOR THE SIX MONTHS ENDED JUNE 30, 1998 AND
IS QUALIFIED IN ITS ENTIRETY BY REFERENCE TO SUCH FINANCIAL STATEMENTS.
</LEGEND>
<MULTIPLIER> 1,000
       
<S>                             <C>
<PERIOD-TYPE>                   6-MOS
<FISCAL-YEAR-END>                          DEC-31-1998
<PERIOD-START>                             JAN-01-1998
<PERIOD-END>                               JUN-30-1998
<CASH>                                          28,735
<INT-BEARING-DEPOSITS>                               0
<FED-FUNDS-SOLD>                                     0
<TRADING-ASSETS>                                     0
<INVESTMENTS-HELD-FOR-SALE>                    217,724
<INVESTMENTS-CARRYING>                          34,925
<INVESTMENTS-MARKET>                            35,015
<LOANS>                                        507,315
<ALLOWANCE>                                      7,548
<TOTAL-ASSETS>                                 804,647
<DEPOSITS>                                     538,343
<SHORT-TERM>                                   157,642
<LIABILITIES-OTHER>                              4,990
<LONG-TERM>                                     12,677
<PREFERRED-MANDATORY>                                0
<PREFERRED>                                          0
<COMMON>                                         6,330
<OTHER-SE>                                      84,695
<TOTAL-LIABILITIES-AND-EQUITY>                 804,647
<INTEREST-LOAN>                                 21,745
<INTEREST-INVEST>                                7,183
<INTEREST-OTHER>                                   304
<INTEREST-TOTAL>                                29,232
<INTEREST-DEPOSIT>                               3,235
<INTEREST-EXPENSE>                              11,631
<INTEREST-INCOME-NET>                           17,601
<LOAN-LOSSES>                                    1,452
<SECURITIES-GAINS>                                   0
<EXPENSE-OTHER>                                 10,440
<INCOME-PRETAX>                                 10,027
<INCOME-PRE-EXTRAORDINARY>                       6,758
<EXTRAORDINARY>                                      0
<CHANGES>                                            0
<NET-INCOME>                                     6,758
<EPS-PRIMARY>                                     1.07
<EPS-DILUTED>                                     1.07
<YIELD-ACTUAL>                                    7.94
<LOANS-NON>                                      1,811
<LOANS-PAST>                                       535
<LOANS-TROUBLED>                                    56
<LOANS-PROBLEM>                                      0
<ALLOWANCE-OPEN>                                 7,524
<CHARGE-OFFS>                                    1,781
<RECOVERIES>                                       353
<ALLOWANCE-CLOSE>                                7,548
<ALLOWANCE-DOMESTIC>                             7,548
<ALLOWANCE-FOREIGN>                                  0
<ALLOWANCE-UNALLOCATED>                            610
        

</TABLE>