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<PAGE> PAGE 4
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<PAGE> PAGE 7
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<PAGE> PAGE 10
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<PAGE> PAGE 11
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<PAGE> PAGE 12
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<PAGE> PAGE 13
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<PAGE> PAGE 14
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<PAGE> PAGE 15
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<PAGE> PAGE 17
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<PAGE> PAGE 20
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<PAGE> PAGE 21
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070 D010700 N
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070 E020700 N
070 F010700 N
070 F020700 N
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070 G020700 N
070 H010700 N
070 H020700 N
070 I010700 N
070 I020700 N
070 J010700 Y
070 J020700 N
070 K010700 Y
070 K020700 N
070 L010700 N
070 L020700 N
070 M010700 N
070 M020700 N
070 N010700 N
070 N020700 N
070 O010700 N
070 O020700 N
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070 P020700 N
070 Q010700 N
070 Q020700 N
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070 R020700 N
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071 C000700 39551
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072 A000700 6
072 B000700 906
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<PAGE> PAGE 22
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<PAGE> PAGE 23
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028 A010800 9881
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049 000800 N
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<PAGE> PAGE 24
060 B000800 Y
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064 A000800 Y
064 B000800 N
070 A010800 N
070 A020800 N
070 B010800 N
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070 C020800 N
070 D010800 N
070 D020800 N
070 E010800 Y
070 E020800 N
070 F010800 N
070 F020800 N
070 G010800 Y
070 G020800 N
070 H010800 N
070 H020800 N
070 I010800 N
070 I020800 N
070 J010800 Y
070 J020800 N
070 K010800 Y
070 K020800 N
070 L010800 N
070 L020800 N
070 M010800 N
070 M020800 N
070 N010800 N
<PAGE> PAGE 25
070 N020800 N
070 O010800 N
070 O020800 N
070 P010800 Y
070 P020800 N
070 Q010800 N
070 Q020800 N
070 R010800 Y
070 R020800 N
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071 B000800 65781
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072 A000800 6
072 B000800 4093
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<PAGE> PAGE 26
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028 A010900 2646
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<PAGE> PAGE 27
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070 A010900 N
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<PAGE> PAGE 28
070 E020900 N
070 F010900 N
070 F020900 N
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070 G020900 N
070 H010900 N
070 H020900 N
070 I010900 N
070 I020900 N
070 J010900 Y
070 J020900 N
070 K010900 Y
070 K020900 N
070 L010900 N
070 L020900 N
070 M010900 N
070 M020900 N
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070 N020900 N
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<PAGE> PAGE 29
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<PAGE> PAGE 30
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<PAGE> PAGE 31
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<PAGE> PAGE 32
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<PAGE> PAGE 33
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SIGNATURE MARYANNE ROEPKE
TITLE TREASURER
<TABLE> <S> <C>
<ARTICLE> 6
<LEGEND>
THIS SCHEDULE CONTAINS SUMMARY FINANCIAL INFORMATION EXTRACTED FROM
THE SEMI-ANNUAL REPORT OF AMERICAN CENTURY CAPITAL PORTFOLIOS, INC. AND
IS QUALIFIED IN ITS ENTIRETY BY REFERENCE TO SUCH REPORT.
</LEGEND>
<CIK> 0000746458
<NAME> AMERICAN CENTURY MUNICIPAL TRUST
<SERIES>
<NUMBER> 11
<NAME> TAX-FREE MONEY MARKET
<S> <C>
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<TOTAL-LIABILITIES> 105,764
<SENIOR-EQUITY> 0
<PAID-IN-CAPITAL-COMMON> 263,124,184
<SHARES-COMMON-STOCK> 263,124,184
<SHARES-COMMON-PRIOR> 283,003,220
<ACCUMULATED-NII-CURRENT> 0
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<ACCUMULATED-NET-GAINS> 227
<OVERDISTRIBUTION-GAINS> 0
<ACCUM-APPREC-OR-DEPREC> 0
<NET-ASSETS> 263,124,411
<DIVIDEND-INCOME> 0
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<EXPENSES-NET> 653,077
<NET-INVESTMENT-INCOME> 3,900,707
<REALIZED-GAINS-CURRENT> (22,748)
<APPREC-INCREASE-CURRENT> 0
<NET-CHANGE-FROM-OPS> 3,877,959
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<NUMBER-OF-SHARES-SOLD> 116,506,888
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<NET-CHANGE-IN-ASSETS> (19,921,434)
<ACCUMULATED-NII-PRIOR> 0
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<PER-SHARE-NAV-END> 1.00
<EXPENSE-RATIO> 0.50
</TABLE>
<TABLE> <S> <C>
<ARTICLE> 6
<LEGEND>
THIS SCHEDULE CONTAINS SUMMARY FINANCIAL INFORMATION EXTRACTED
FROM THE SEMI-ANNUAL REPORT OF AMERICAN CENTURY MUNICIPAL FUNDS
AND IS QUALIFIED IN ITS ENTIRETY BY REFERENCE TO SUCH REPORT.
</LEGEND>
<CIK> 0000746458
<NAME> AMERICAN CENTURY MUNICIPAL TRUST
<SERIES>
<NUMBER> 21
<NAME> FLORIDA MUNICIPAL MONEY MARKET FUND
<S> <C>
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<PERIOD-END> NOV-30-1999
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<OTHER-ITEMS-ASSETS> 0
<TOTAL-ASSETS> 86,195,080
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<SENIOR-LONG-TERM-DEBT> 0
<OTHER-ITEMS-LIABILITIES> 765,981
<TOTAL-LIABILITIES> 5,269,127
<SENIOR-EQUITY> 0
<PAID-IN-CAPITAL-COMMON> 80,949,905
<SHARES-COMMON-STOCK> 80,949,905
<SHARES-COMMON-PRIOR> 87,509,456
<ACCUMULATED-NII-CURRENT> (23,952)
<OVERDISTRIBUTION-NII> 0
<ACCUMULATED-NET-GAINS> 0
<OVERDISTRIBUTION-GAINS> 0
<ACCUM-APPREC-OR-DEPREC> 0
<NET-ASSETS> 80,925,953
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<EXPENSES-NET> 207,710
<NET-INVESTMENT-INCOME> 1,236,734
<REALIZED-GAINS-CURRENT> (23,952)
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<NET-CHANGE-FROM-OPS> 1,212,782
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<DISTRIBUTIONS-OF-GAINS> 0
<DISTRIBUTIONS-OTHER> 0
<NUMBER-OF-SHARES-SOLD> 23,121,723
<NUMBER-OF-SHARES-REDEEMED> 30,801,943
<SHARES-REINVESTED> 1,120,668
<NET-CHANGE-IN-ASSETS> (6,583,504)
<ACCUMULATED-NII-PRIOR> 0
<ACCUMULATED-GAINS-PRIOR> 0
<OVERDISTRIB-NII-PRIOR> 0
<OVERDIST-NET-GAINS-PRIOR> 0
<GROSS-ADVISORY-FEES> 205,188
<INTEREST-EXPENSE> 0
<GROSS-EXPENSE> 207,710
<AVERAGE-NET-ASSETS> 83,210,636
<PER-SHARE-NAV-BEGIN> 1.00
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<PER-SHARE-NAV-END> 1.00
<EXPENSE-RATIO> 0.50
</TABLE>
<TABLE> <S> <C>
<ARTICLE> 6
<LEGEND>
THIS SCHEDULE CONTAINS SUMMARY FINANCIAL INFORMATION EXTRACTED
FROM THE SEMI-ANNUAL REPORT OF AMERICAN CENTURY MUNICIPAL FUNDS
AND IS QUALIFIED IN ITS ENTIRETY BY REFERENCE TO SUCH REPORT.
</LEGEND>
<CIK> 0000746458
<NAME> AMERICAN CENTURY MUNICIPAL TRUST
<SERIES>
<NUMBER> 41
<NAME> FLORIDA INTERMEDIATE-TERM MUNICIPAL FUND
<S> <C>
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<ACCUMULATED-NII-CURRENT> 0
<OVERDISTRIBUTION-NII> 0
<ACCUMULATED-NET-GAINS> (346,686)
<OVERDISTRIBUTION-GAINS> 0
<ACCUM-APPREC-OR-DEPREC> (407,046)
<NET-ASSETS> 48,987,802
<DIVIDEND-INCOME> 0
<INTEREST-INCOME> 1,092,067
<OTHER-INCOME> 0
<EXPENSES-NET> 115,675
<NET-INVESTMENT-INCOME> 976,392
<REALIZED-GAINS-CURRENT> (388,178)
<APPREC-INCREASE-CURRENT> (914,330)
<NET-CHANGE-FROM-OPS> (326,116)
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<DISTRIBUTIONS-OF-INCOME> 976,392
<DISTRIBUTIONS-OF-GAINS> 0
<DISTRIBUTIONS-OTHER> 0
<NUMBER-OF-SHARES-SOLD> 1,844,263
<NUMBER-OF-SHARES-REDEEMED> 1,321,668
<SHARES-REINVESTED> 53,968
<NET-CHANGE-IN-ASSETS> 4,609,210
<ACCUMULATED-NII-PRIOR> 0
<ACCUMULATED-GAINS-PRIOR> 315,971
<OVERDISTRIB-NII-PRIOR> 0
<OVERDIST-NET-GAINS-PRIOR> 0
<GROSS-ADVISORY-FEES> 114,303
<INTEREST-EXPENSE> 0
<GROSS-EXPENSE> 115,675
<AVERAGE-NET-ASSETS> 45,186,179
<PER-SHARE-NAV-BEGIN> 10.50
<PER-SHARE-NII> 0.22
<PER-SHARE-GAIN-APPREC> (0.30)
<PER-SHARE-DIVIDEND> 0.22
<PER-SHARE-DISTRIBUTIONS> 0.00
<RETURNS-OF-CAPITAL> 0.00
<PER-SHARE-NAV-END> 10.20
<EXPENSE-RATIO> 0.51
</TABLE>
<TABLE> <S> <C>
<ARTICLE> 6
<LEGEND>
THIS SCHEDULE CONTAINS SUMMARY FINANCIAL INFORMATION EXTRACTED FROM
THE SEMI-ANNUAL REPORT OF AMERICAN CENTURY CAPITAL PORTFOLIOS, INC. AND
IS QUALIFIED IN ITS ENTIRETY BY REFERENCE TO SUCH REPORT.
</LEGEND>
<CIK> 0000746458
<NAME> AMERICAN CENTURY MUNICIPAL TRUST
<SERIES>
<NUMBER> 51
<NAME> ARIZONA INTERMEDIATE-TERM MUNICIPAL
<S> <C>
<PERIOD-TYPE> 6-MOS
<FISCAL-YEAR-END> MAY-31-2000
<PERIOD-END> NOV-30-1999
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</TABLE>
<TABLE> <S> <C>
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<LEGEND>
THIS SCHEDULE CONTAINS SUMMARY FINANCIAL INFORMATION EXTRACTED FROM
THE SEMI-ANNUAL REPORT OF AMERICAN CENTURY CAPITAL PORTFOLIOS, INC. AND
IS QUALIFIED IN ITS ENTIRETY BY REFERENCE TO SUCH REPORT.
</LEGEND>
<CIK> 0000746458
<NAME> AMERICAN CENTURY MUNICIPAL TRUST
<SERIES>
<NUMBER> 71
<NAME> LIMITED-TERM TAX-FREE FUND
<MULTIPLIER> 1000
<S> <C>
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</TABLE>
<TABLE> <S> <C>
<ARTICLE> 6
<LEGEND>
THIS SCHEDULE CONTAINS SUMMARY FINANCIAL INFORMATION EXTRACTED FROM
THE SEMI-ANNUAL REPORT OF AMERICAN CENTURY CAPITAL PORTFOLIOS, INC. AND
IS QUALIFIED IN ITS ENTIRETY BY REFERENCE TO SUCH REPORT.
</LEGEND>
<CIK> 0000746458
<NAME> AMERICAN CENTURY MUNICIPAL TRUST
<SERIES>
<NUMBER> 81
<NAME> INTERMEDIATE-TERM TAX-FREE FUND
<MULTIPLIER> 1000
<S> <C>
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<PERIOD-END> NOV-30-1999
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<TABLE> <S> <C>
<ARTICLE> 6
<LEGEND>
THIS SCHEDULE CONTAINS SUMMARY FINANCIAL INFORMATION EXTRACTED FROM
THE SEMI-ANNUAL REPORT OF AMERICAN CENTURY MUNICIPAL TRUST AND
IS QUALIFIED IN ITS ENTIRETY BY REFERENCE TO SUCH REPORT.
</LEGEND>
<CIK> 0000746458
<NAME> AMERICAN CENTURY MUNICIPAL TRUST
<SERIES>
<NUMBER> 91
<NAME> LONG-TERM TAX-FREE FUND
<MULTIPLIER> 1000
<S> <C>
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</TABLE>
<TABLE> <S> <C>
<ARTICLE> 6
<LEGEND>
THIS SCHEDULE CONTAINS SUMMARY FINANCIAL INFORMATION EXTRACTED FROM
THE SEMI-ANNUAL REPORT OF AMERICAN CENTURY MUNICIPAL TRUST AND
IS QUALIFIED IN ITS ENTIRETY BY REFERENCE TO SUCH REPORT.
</LEGEND>
<CIK> 0000746458
<NAME> AMERICAN CENTURY MUNICIPAL TRUST
<SERIES>
<NUMBER> 10
<NAME> HIGH YIELD MUNICIPAL
<MULTIPLIER> 1000
<S> <C>
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</TABLE>
