<TABLE> <S> <C>

<PAGE>
<ARTICLE> 5
<LEGEND>
This schedule contains summary financial information extracted from Walker
Interactive Systems, Inc. annual report on Form 10-K for the year ended December
31, 1997 and the quarterly reports on form 10-Q for the periods ended March 31,
1997, June 30, 1997 and September 30, 1997 and is qualified in its entirety by
reference to such financial statements.
</LEGEND>
<RESTATED> 
<MULTIPLIER> 1,000
       
<S>                             <C>                     <C>                     <C>                     <C>
<PERIOD-TYPE>                   YEAR                   3-MOS                   6-MOS                   9-MOS
<FISCAL-YEAR-END>                          DEC-31-1997             DEC-31-1997             DEC-31-1997             DEC-31-1997
<PERIOD-START>                             JAN-01-1997             JAN-01-1997             JAN-01-1997             JAN-01-1997
<PERIOD-END>                               DEC-31-1997             MAR-31-1997             JUN-30-1997             SEP-30-1997
<CASH>                                           7,646                   6,504                   9,868                  11,755
<SECURITIES>                                    20,044                  26,739                  24,628                  19,286
<RECEIVABLES>                                   24,483                  16,207                  16,086                  17,555
<ALLOWANCES>                                     1,376                   1,755                   1,401                   1,401
<INVENTORY>                                          0                       0                       0                       0
<CURRENT-ASSETS>                                46,447                  41,183                  43,312                  42,852
<PP&E>                                          25,590                  21,311                  22,547                  22,274
<DEPRECIATION>                                  20,991                  17,187                  18,473                  18,473
<TOTAL-ASSETS>                                  91,334                  80,133                  82,387                  80,858
<CURRENT-LIABILITIES>                           34,849                  25,641                  26,534                  26,028
<BONDS>                                              0                       0                       0                       0
<PREFERRED-MANDATORY>                                0                       0                       0                       0
<PREFERRED>                                          0                       0                       0                       0
<COMMON>                                            14                      14                      14                      14
<OTHER-SE>                                      51,675                  47,213                  48,664                  48,639
<TOTAL-LIABILITY-AND-EQUITY>                    91,334                  80,133                  82,387                  80,858
<SALES>                                         71,409                  17,073                  33,334                  49,601
<TOTAL-REVENUES>                                71,409                  17,073                  33,334                  49,601
<CGS>                                           33,335                   7,764                  15,517                  24,056
<TOTAL-COSTS>                                   75,428                  16,539                  32,736                  49,314
<OTHER-EXPENSES>                                     0                       0                       0                       0
<LOSS-PROVISION>                                     0                       0                       0                       0
<INTEREST-EXPENSE>                                   0                       0                       0                       0
<INCOME-PRETAX>                                 (2,179)                  1,038                   1,592                   1,732
<INCOME-TAX>                                     1,298                     362                     557                     605
<INCOME-CONTINUING>                                  0                       0                       0                       0
<DISCONTINUED>                                       0                       0                       0                       0
<EXTRAORDINARY>                                      0                       0                       0                       0
<CHANGES>                                            0                       0                       0                       0
<NET-INCOME>                                    (3,477)                    676                   1,035                   1,127
<EPS-PRIMARY>                                    (0.26)<F1>               0.05<F1>                0.08<F1>                0.09<F1>
<EPS-DILUTED>                                    (0.26)                   0.05                    0.07                    0.08
        

<FN>
<F1> BASIC EARNINGS PER SHARE ARE REPORTED UNDER EDGAR TAG "EPS-PRIMARY".
</FN>

</TABLE>