[ARTICLE] 6
[CIK] 777547
[NAME] Oppenheimer Discovery Fund - Y
<TABLE>
<S> <C>
[PERIOD-TYPE] 6-MOS
[FISCAL-YEAR-END] SEP-30-2000
[PERIOD-START] OCT-01-1999
[PERIOD-END] MAR-31-2000
[INVESTMENTS-AT-COST] 1,517,889,894
[INVESTMENTS-AT-VALUE] 1,999,655,438
[RECEIVABLES] 134,838,962
[ASSETS-OTHER] 58,938
[OTHER-ITEMS-ASSETS] 0
[TOTAL-ASSETS] 2,134,553,338
[PAYABLE-FOR-SECURITIES] 84,616,014
[SENIOR-LONG-TERM-DEBT] 0
[OTHER-ITEMS-LIABILITIES] 19,673,932
[TOTAL-LIABILITIES] 104,289,946
[SENIOR-EQUITY] 0
[PAID-IN-CAPITAL-COMMON] 986,101,454
[SHARES-COMMON-STOCK] 1,416,894
[SHARES-COMMON-PRIOR] 892,212
[ACCUMULATED-NII-CURRENT] (7,483,746)
[OVERDISTRIBUTION-NII] 0
[ACCUMULATED-NET-GAINS] 569,886,206
[OVERDISTRIBUTION-GAINS] 0
[ACCUM-APPREC-OR-DEPREC] 481,759,478
[NET-ASSETS] 108,751,113
[DIVIDEND-INCOME] 419,218
[INTEREST-INCOME] 3,285,068
[OTHER-INCOME] 0
[EXPENSES-NET] 10,953,861
[NET-INVESTMENT-INCOME] (7,249,575)
[REALIZED-GAINS-CURRENT] 572,286,391
[APPREC-INCREASE-CURRENT] 275,303,784
[NET-CHANGE-FROM-OPS] 840,340,600
[EQUALIZATION] 0
[DISTRIBUTIONS-OF-INCOME] 0
[DISTRIBUTIONS-OF-GAINS] 2,425,868
[DISTRIBUTIONS-OTHER] 0
[NUMBER-OF-SHARES-SOLD] 1,093,751
[NUMBER-OF-SHARES-REDEEMED] 610,801
[SHARES-REINVESTED] 41,732
[NET-CHANGE-IN-ASSETS] 988,557,918
[ACCUMULATED-NII-PRIOR] (234,171)
[ACCUMULATED-GAINS-PRIOR] 66,413,804
[OVERDISTRIB-NII-PRIOR] 0
[OVERDIST-NET-GAINS-PRIOR] 0
[GROSS-ADVISORY-FEES] 5,175,263
[INTEREST-EXPENSE] 0
[GROSS-EXPENSE] 10,984,005
[AVERAGE-NET-ASSETS] 68,000,000
[PER-SHARE-NAV-BEGIN] 43.92
[PER-SHARE-NII] (0.40)
[PER-SHARE-GAIN-APPREC] 36.12
[PER-SHARE-DIVIDEND] 0.00
[PER-SHARE-DISTRIBUTIONS] 2.89
[RETURNS-OF-CAPITAL] 0.00
[PER-SHARE-NAV-END] 76.75
[EXPENSE-RATIO] 0.96
[AVG-DEBT-OUTSTANDING] 0
[AVG-DEBT-PER-SHARE] 0.00
</TABLE>
