<PAGE>   1
                                                                      EXHIBIT 11


             FRESENIUS MEDICAL CARE HOLDINGS, INC. AND SUBSIDIARIES
        WEIGHTED AVERAGE NUMBER OF SHARES AND EARNINGS USED IN PER SHARE
                                   COMPUTATION
                        (DOLLARS AND SHARES IN THOUSANDS)

<TABLE>
<CAPTION>
                                                                            THREE MONTHS ENDED              NINE MONTHS ENDED
                                                                               SEPTEMBER 30,                  SEPTEMBER 30,
                                                                        -------------------------       -------------------------
                                                                           1999            1998            1999            1998
                                                                           ----            ----            ----            ----
<S>                                                                     <C>               <C>           <C>              <C>
        The weighted average number of shares of
                                                                        ---------         -------       ---------        --------
          Common Stock were as follows ............................        90,000          90,000          90,000          90,000
                                                                        =========         =======       =========        ========
</TABLE>

Income (loss) used in the computation of earnings per share were as follows:

<TABLE>
<CAPTION>
                                                                            THREE MONTHS ENDED              NINE MONTHS ENDED
                                                                               SEPTEMBER 30,                  SEPTEMBER 30,
                                                                        -------------------------       -------------------------
        CONTINUED OPERATIONS                                               1999            1998            1999            1998
                                                                           ----            ----            ----            ----
<S>                                                                     <C>               <C>           <C>             <C>
        Net earnings (loss)........................................     $(387,205)        $14,304        (348,174)      $  36,920

        Dividends paid on preferred stocks.........................          (130)           (130)           (390)           (390)
                                                                        ---------         -------       ---------       ---------
                                                                        ---------         -------       ---------       ---------
        Income (loss) used in per share computation of earnings....     $(387,335)        $14,174        (348,564)      $  36,530
                                                                        =========         =======       =========       =========

        Basic and fully dilutive earnings (loss) per share.........     $   (4.30)        $  0.16       $   (3.87)      $    0.41
                                                                        =========         =======       =========       =========
</TABLE>


<TABLE>
<CAPTION>
                                                                            THREE MONTHS ENDED              NINE MONTHS ENDED
                                                                               SEPTEMBER 30,                  SEPTEMBER 30,
                                                                        -------------------------       -------------------------
        DISCONTINUED OPERATIONS                                            1999            1998            1999            1998
                                                                           ----            ----            ----            ----
<S>                                                                     <C>               <C>           <C>             <C>

        Net loss...................................................     $      --         $     0              --       $(105,897)

        Dividends paid on preferred stocks.........................            --              --              --              --
                                                                        ---------         -------       ---------       ---------
                                                                        ---------         -------       ---------       ---------
        Loss used in per share computation of earnings.............     $      --         $    --              --       $(105,897)
                                                                        =========         =======       =========       =========

        Basic and fully dilutive loss per share....................     $      --         $    --              --       $   (1.18)
                                                                        =========         =======       =========       =========
</TABLE>


<TABLE>
<CAPTION>
                                                                            THREE MONTHS ENDED              NINE MONTHS ENDED
                                                                               SEPTEMBER 30,                  SEPTEMBER 30,
        CUMULATIVE EFFECT OF ACCOUNTING CHANGE                             1999            1998            1999            1998
                                                                           ----            ----            ----            ----
<S>                                                                     <C>               <C>           <C>             <C>

        Cumulative effect of accounting change.....................     $      --         $    --              --       $  (4,890)

        Dividends paid on preferred stocks.........................            --              --              --              --
                                                                        ---------         -------       ---------       ---------
                                                                        ---------         -------       ---------       ---------
        Loss used in per share computation of earnings.............     $      --         $    --              --       $  (4,890)
                                                                        =========         =======       =========       =========

        Basic and fully dilutive loss per share....................     $      --         $    --              --       $   (0.05)
                                                                        =========         =======       =========       =========
</TABLE>

<TABLE>
<CAPTION>
                                                                            THREE MONTHS ENDED              NINE MONTHS ENDED
                                                                               SEPTEMBER 30,                  SEPTEMBER 30,
        CONSOLIDATED                                                       1999            1998            1999            1998
                                                                           ----            ----            ----            ----
<S>                                                                     <C>               <C>           <C>             <C>
        Net earnings (loss)........................................     $(387,205)        $14,304        (348,174)      $ (73,867)

        Dividends paid on preferred stocks.........................          (130)           (130)           (390)           (390)
                                                                        ---------         -------       ---------       ---------
                                                                        ---------         -------       ---------       ---------
        Income (loss) used in per share computation of earnings....     $(387,335)        $14,174        (348,564)      $ (74,257)
                                                                        =========         =======       =========       =========

        Basic and fully dilutive earnings (loss) per share.........     $   (4.30)        $  0.16           (3.87)      $   (0.82)
                                                                        =========         =======       =========       =========
</TABLE>