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SIGNATURE GEORGE C. BOWEN
TITLE TREASURER
WARNING: THE EDGAR SYSTEM ENCOUNTERED ERROR(S) WHILE PROCESSING THIS SCHEDULE.
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WARNING: THE EDGAR SYSTEM ENCOUNTERED ERROR(S) WHILE PROCESSING THIS SCHEDULE.
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<OVERDISTRIBUTION-NII> 0
<ACCUMULATED-NET-GAINS> 558,207
<OVERDISTRIBUTION-GAINS> 0
<ACCUM-APPREC-OR-DEPREC> 7,773,802
<NET-ASSETS> 97,715,504
<DIVIDEND-INCOME> 0
<INTEREST-INCOME> 3,189,643
<OTHER-INCOME> 0
<EXPENSES-NET> 623,105
<NET-INVESTMENT-INCOME> 2,566,538
<REALIZED-GAINS-CURRENT> 602,810
<APPREC-INCREASE-CURRENT> 1,618,378
<NET-CHANGE-FROM-OPS> 4,787,726
<EQUALIZATION> 0
<DISTRIBUTIONS-OF-INCOME> 2,241,710
<DISTRIBUTIONS-OF-GAINS> 646,115
<DISTRIBUTIONS-OTHER> 0
<NUMBER-OF-SHARES-SOLD> 508,759
<NUMBER-OF-SHARES-REDEEMED> 311,610
<SHARES-REINVESTED> 119,433
<NET-CHANGE-IN-ASSETS> 12,072,683
<ACCUMULATED-NII-PRIOR> 310,788
<ACCUMULATED-GAINS-PRIOR> 770,265
<OVERDISTRIB-NII-PRIOR> 0
<OVERDIST-NET-GAINS-PRIOR> 0
<GROSS-ADVISORY-FEES> 263,557
<INTEREST-EXPENSE> 0
<GROSS-EXPENSE> 623,105
<AVERAGE-NET-ASSETS> 94,595,529
<PER-SHARE-NAV-BEGIN> 17.72
<PER-SHARE-NII> 0.40
<PER-SHARE-GAIN-APPREC> 0.34
<PER-SHARE-DIVIDEND> 0.43
<PER-SHARE-DISTRIBUTIONS> 0.12
<RETURNS-OF-CAPITAL> 0.00
<PER-SHARE-NAV-END> 17.91
<EXPENSE-RATIO> 0.89
<AVG-DEBT-OUTSTANDING> 0
<AVG-DEBT-PER-SHARE> 0.00
</TABLE>
WARNING: THE EDGAR SYSTEM ENCOUNTERED ERROR(S) WHILE PROCESSING THIS SCHEDULE.
<TABLE> <S> <C>
<ARTICLE> 6
<CIK> 799102
<NAME> Oppenheimer Insured Municipal Fund - B
<SERIES>
<NUMBER> 2
<NAME> Oppenheimer Municipal Fund
<S> <C>
<PERIOD-TYPE> 6-MOS
<FISCAL-YEAR-END> SEP-30-1998
<PERIOD-START> OCT-01-1997
<PERIOD-END> MAR-31-1998
<INVESTMENTS-AT-COST> 121,882,395
<INVESTMENTS-AT-VALUE> 129,626,510
<RECEIVABLES> 4,065,611
<ASSETS-OTHER> 20,080
<OTHER-ITEMS-ASSETS> 357,970
<TOTAL-ASSETS> 134,070,171
<PAYABLE-FOR-SECURITIES> 7,888,781
<SENIOR-LONG-TERM-DEBT> 0
<OTHER-ITEMS-LIABILITIES> 529,498
<TOTAL-LIABILITIES> 8,418,279
<SENIOR-EQUITY> 0
<PAID-IN-CAPITAL-COMMON> 117,162,752
<SHARES-COMMON-STOCK> 1,357,430
<SHARES-COMMON-PRIOR> 1,126,768
<ACCUMULATED-NII-CURRENT> 157,131
<OVERDISTRIBUTION-NII> 0
<ACCUMULATED-NET-GAINS> 558,207
<OVERDISTRIBUTION-GAINS> 0
<ACCUM-APPREC-OR-DEPREC> 7,773,802
<NET-ASSETS> 24,323,686
<DIVIDEND-INCOME> 0
<INTEREST-INCOME> 3,189,643
<OTHER-INCOME> 0
<EXPENSES-NET> 623,105
<NET-INVESTMENT-INCOME> 2,566,538
<REALIZED-GAINS-CURRENT> 602,810
<APPREC-INCREASE-CURRENT> 1,618,378
<NET-CHANGE-FROM-OPS> 4,787,726
<EQUALIZATION> 0
<DISTRIBUTIONS-OF-INCOME> 433,732
<DISTRIBUTIONS-OF-GAINS> 149,337
<DISTRIBUTIONS-OTHER> 0
<NUMBER-OF-SHARES-SOLD> 295,797
<NUMBER-OF-SHARES-REDEEMED> 87,227
<SHARES-REINVESTED> 22,092
<NET-CHANGE-IN-ASSETS> 12,072,683
<ACCUMULATED-NII-PRIOR> 310,788
<ACCUMULATED-GAINS-PRIOR> 770,265
<OVERDISTRIB-NII-PRIOR> 0
<OVERDIST-NET-GAINS-PRIOR> 0
<GROSS-ADVISORY-FEES> 263,557
<INTEREST-EXPENSE> 0
<GROSS-EXPENSE> 623,105
<AVERAGE-NET-ASSETS> 22,028,181
<PER-SHARE-NAV-BEGIN> 17.73
<PER-SHARE-NII> 0.32
<PER-SHARE-GAIN-APPREC> 0.35
<PER-SHARE-DIVIDEND> 0.36
<PER-SHARE-DISTRIBUTIONS> 0.12
<RETURNS-OF-CAPITAL> 0.00
<PER-SHARE-NAV-END> 17.92
<EXPENSE-RATIO> 1.64
<AVG-DEBT-OUTSTANDING> 0
<AVG-DEBT-PER-SHARE> 0.00
</TABLE>
<TABLE> <S> <C>
<ARTICLE> 6
<CIK> 799102
<NAME> Oppenheimer Insured Municipal Fund - C
<SERIES>
<NUMBER> 2
<NAME> Oppenheimer Municipal Fund
<S> <C>
<PERIOD-TYPE> 6-MOS
<FISCAL-YEAR-END> SEP-30-1998
<PERIOD-START> OCT-01-1997
<PERIOD-END> MAR-31-1998
<INVESTMENTS-AT-COST> 121,882,395
<INVESTMENTS-AT-VALUE> 129,626,510
<RECEIVABLES> 4,065,611
<ASSETS-OTHER> 20,080
<OTHER-ITEMS-ASSETS> 357,970
<TOTAL-ASSETS> 134,070,171
<PAYABLE-FOR-SECURITIES> 7,888,781
<SENIOR-LONG-TERM-DEBT> 0
<OTHER-ITEMS-LIABILITIES> 529,498
<TOTAL-LIABILITIES> 8,418,279
<SENIOR-EQUITY> 0
<PAID-IN-CAPITAL-COMMON> 117,162,752
<SHARES-COMMON-STOCK> 201,702
<SHARES-COMMON-PRIOR> 144,171
<ACCUMULATED-NII-CURRENT> 157,131
<OVERDISTRIBUTION-NII> 0
<ACCUMULATED-NET-GAINS> 558,207
<OVERDISTRIBUTION-GAINS> 0
<ACCUM-APPREC-OR-DEPREC> 7,773,802
<NET-ASSETS> 3,612,702
<DIVIDEND-INCOME> 0
<INTEREST-INCOME> 3,189,643
<OTHER-INCOME> 0
<EXPENSES-NET> 623,105
<NET-INVESTMENT-INCOME> 2,566,538
<REALIZED-GAINS-CURRENT> 602,810
<APPREC-INCREASE-CURRENT> 1,618,378
<NET-CHANGE-FROM-OPS> 4,787,726
<EQUALIZATION> 0
<DISTRIBUTIONS-OF-INCOME> 60,154
<DISTRIBUTIONS-OF-GAINS> 19,416
<DISTRIBUTIONS-OTHER> 0
<NUMBER-OF-SHARES-SOLD> 64,395
<NUMBER-OF-SHARES-REDEEMED> 10,440
<SHARES-REINVESTED> 3,576
<NET-CHANGE-IN-ASSETS> 12,072,683
<ACCUMULATED-NII-PRIOR> 310,788
<ACCUMULATED-GAINS-PRIOR> 770,265
<OVERDISTRIB-NII-PRIOR> 0
<OVERDIST-NET-GAINS-PRIOR> 0
<GROSS-ADVISORY-FEES> 263,557
<INTEREST-EXPENSE> 0
<GROSS-EXPENSE> 623,105
<AVERAGE-NET-ASSETS> 3,082,817
<PER-SHARE-NAV-BEGIN> 17.72
<PER-SHARE-NII> 0.30
<PER-SHARE-GAIN-APPREC> 0.37
<PER-SHARE-DIVIDEND> 0.36
<PER-SHARE-DISTRIBUTIONS> 0.12
<RETURNS-OF-CAPITAL> 0.00
<PER-SHARE-NAV-END> 17.91
<EXPENSE-RATIO> 1.64
<AVG-DEBT-OUTSTANDING> 0
<AVG-DEBT-PER-SHARE> 0.00
</TABLE>
As of November 4, 1997, in order to conform book and tax bases, the Fund
began amortization of premiums on securities for book purposes.
Accordingly, during the six months ended March 31, 1998, amounts have been
reclassified to reflect an increase in undistributed net investment income
of $178,283, an increase in unrealized appreciation on investments of
$719,029 and a decrease in paid-in capital of $897,312. For bonds acquired
after April 30, 1993, on disposition or maturity, taxable ordinary income
is recognized to the extent of the lesser of gain or market discount that
would have accrued over the holding period. Realized gains and losses on
investments and unrealized appreciation and depreciation are determined on
an identified cost basis, which is the same basis used for federal income
tax purposes.
As of November 4, 1997, in order to conform book and tax bases, the Fund
began amortization of premiums on securities for book purposes.
Accordingly, during the six months ended March 31, 1998, amounts have been
reclassified to reflect a decrease in undistributed net investment income
of $15,401, an increase in unrealized appreciation on investments of
$581,763 and an increase in paid-in capital of $597,164. For bonds acquired
after April 30, 1993, on disposition or maturity, taxable ordinary income
is recognized to the extent of the lesser of gain or market discount that
would have accrued over the holding period. Realized gains and losses on
investments and unrealized appreciation and depreciation are determined on
an identified cost basis, which is the same basis used for federal income
tax purposes.