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                                                                     EXHIBIT 11A

                       GATX CORPORATION AND SUBSIDIARIES

           COMPUTATION OF BASIC NET INCOME PER SHARE OF COMMON STOCK
                    (IN MILLIONS, EXCEPT PER SHARE AMOUNTS)



<TABLE>
<CAPTION>
                                                                      THREE MONTHS ENDED                 NINE MONTHS ENDED
                                                                         SEPTEMBER 30                      SEPTEMBER 30
                                                                -------------------------------    ------------------------------
                                                                    1999              1998             1999             1998
                                                                -------------      ------------    --------------    ------------
<S>                                                               <C>              <C>             <C>               <C>
Average number of shares of common stock
 outstanding                                                         49.5              49.2               49.4            49.1

Net income                                                        $  42.2            $ 38.1         $    119.5        $  106.3

Deduct - Dividends paid and accrued on preferred
 stock                                                                  -                 -                 -               -
                                                                -------------      ------------    --------------    ------------

Net income, as adjusted                                           $  42.2              38.1         $    119.5        $  106.3
                                                                =============      ============    ==============    ============

Basic net income per share                                        $    .85           $   .78        $      2.42       $    2.16
                                                                =============      ============    ==============    ============
</TABLE>






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