<PAGE>
 
                               ZAPATA CORPORATION
 
            NOTES TO CONSOLIDATED FINANCIAL STATEMENTS--(CONTINUED)
 
NOTE 15. OIL AND GAS OPERATIONS (UNAUDITED)--(CONTINUED)
 
            STANDARDIZED MEASURE OF DISCOUNTED FUTURE NET CASH FLOWS
                          RELATING TO PROVED RESERVES
 

<TABLE>
<CAPTION>
                                                       UNITED
                                                       STATES  BOLIVIA  TOTAL
                                                      -------- ------- --------
                                                           (IN THOUSANDS)
<S>                                                   <C>      <C>     <C>
1995
  Estimated future cash flows
    Revenues from hydrocarbon sales.................. $     -- $46,512 $ 46,512
    Production costs.................................       --  18,621   18,621
    Development costs................................       --     775      775
                                                      -------- ------- --------
  Future net cash flows before income taxes..........       --  27,116   27,116
  Estimated income tax payments......................       --   8,356    8,356
                                                      -------- ------- --------
  Future net cash flows..............................       --  18,760   18,760
  10% discount.......................................       --   8,359    8,359
                                                      -------- ------- --------
  Standardized measure of discounted future net cash
   flows............................................. $     -- $10,401 $ 10,401
                                                      ======== ======= ========
1994
  Estimated future cash flows
    Revenues from hydrocarbon sales.................. $ 51,380 $44,473 $ 95,853
    Production costs.................................   19,132  12,010   31,142
    Development costs................................    7,899     825    8,724
    Dismantlement and abandonment....................    7,924            7,924
                                                      -------- ------- --------
  Future net cash flows before income taxes..........   16,425  31,638   48,063
  Estimated income tax payments......................      941  10,165   11,106
                                                      -------- ------- --------
  Future net cash flows..............................   15,484  21,473   36,957
  10% discount.......................................    1,570  10,142   11,712
                                                      -------- ------- --------
  Standardized measure of discounted future net cash
   flows............................................. $ 13,914 $11,331 $ 25,245
                                                      ======== ======= ========
1993
  Estimated future cash flows
    Revenues from hydrocarbon sales.................. $104,889 $    -- $104,889
    Production costs.................................   28,399      --   28,399
    Development costs................................   14,960      --   14,960
                                                      -------- ------- --------
  Future net cash flows before income taxes..........   61,530      --   61,530
  Estimated income tax payments......................   11,283      --   11,283
                                                      -------- ------- --------
  Future net cash flows..............................   50,247      --   50,247
  10% discount.......................................   12,345      --   12,345
                                                      -------- ------- --------
  Standardized measure of discounted future net cash
   flows............................................. $ 37,902 $    -- $ 37,902
                                                      ======== ======= ========
</TABLE>

 
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