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                                                                      EXHIBIT 11


                         CMP MEDIA INC. AND SUBSIDIARIES
                     COMPUTATION OF PRO FORMA NET INCOME PER
                       COMMON AND COMMON EQUIVALENT SHARE
                      (IN THOUSANDS, EXCEPT SHARE AMOUNTS)
                                    UNAUDITED



<TABLE>
<CAPTION>
                                                                              THREE MONTHS ENDED          SIX MONTHS ENDED
                                                                                   JUNE 30,                    JUNE 30,
                                                                          -------------------------   -------------------------
                                                                             1996          1997          1996          1997
                                                                          -----------   -----------   -----------   -----------
<S>                                                                       <C>           <C>           <C>           <C>
Historical income before provision for income taxes                       $     9,201   $    11,507   $     8,399   $     7,516
Pro forma provision for income taxes assuming
   change in tax status to C corporation prior to
   January 1, 1996                                                              3,880         5,017         3,542         3,277
                                                                          -----------   -----------   -----------   -----------
Pro forma net income applicable to common and
   common equivalent shares                                               $     5,321   $     6,490   $     4,857   $     4,239
                                                                          ===========   ===========   ===========   ===========

Primary shares:
   Weighted average number of common stock and common
    stock equivalents outstanding:
      Common stock                                                         18,874,570    18,874,570    18,874,570    18,874,570
      Options                                                               1,291,753     1,291,753     1,291,753     1,291,753
      Shares required to be issued to pay S Corporation
        Distribution                                                        1,727,273     1,727,273     1,727,273     1,727,273
      Shares required to be issued to pay S corporation
        distributions in excess of earnings during the previous
        twelve months                                                         468,181       468,181       468,181       468,181
                                                                          -----------   -----------   -----------   -----------
                                                                           22,361,777    22,361,777    22,361,777    22,361,777
                                                                          ===========   ===========   ===========   ===========

Fully diluted shares:
   Weighted average number of common stock and common stock equivalents
   outstanding:
      Common stock                                                         18,874,570    18,874,570    18,874,570    18,874,570
      Options                                                               1,291,753     1,291,753     1,291,753     1,291,753
      Shares required to be issued to pay S Corporation
        Distribution                                                        1,727,273     1,727,273     1,727,273     1,727,273
      Shares required to be issued to pay S corporation
        distributions in excess of earnings during the previous
        twelve months                                                         468,181       468,181       468,181       468,181
                                                                          -----------   -----------   -----------   -----------
                                                                           22,361,777    22,361,777    22,361,777    22,361,777
                                                                          ===========   ===========   ===========   ===========
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