<ARTICLE>                           5
<CIK>                               0000869801
<NAME>                              GEODYNE INST/PEN ENERGY INCOME LTD PSHP P-6

                                   
<PERIOD-TYPE>                       9-MOS
<FISCAL-YEAR-END>                   DEC-31-1999
<PERIOD-START>                      JAN-01-1999
<PERIOD-END>                        SEP-30-1999
<CASH>                                   311,145
<SECURITIES>                                   0
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<SALES>                                  996,224
<TOTAL-REVENUES>                       1,002,721
<CGS>                                          0
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<EPS-BASIC>                               3.68
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