<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> 0000908186
<NAME> AMERICAN CENTURY CAPITAL PORTFOLIOS, INC.
<SERIES>
<NUMBER> 51
<NAME> EQUITY INDEX FUND -INVESTOR CLASS
<S> <C>
<PERIOD-TYPE> 6-MOS
<FISCAL-YEAR-END> MAR-31-2000
<PERIOD-END> SEP-30-2000
<INVESTMENTS-AT-COST> 439,631,638
<INVESTMENTS-AT-VALUE> 492,452,067
<RECEIVABLES> 400,728
<ASSETS-OTHER> 0
<OTHER-ITEMS-ASSETS> 0
<TOTAL-ASSETS> 492,852,795
<PAYABLE-FOR-SECURITIES> 0
<SENIOR-LONG-TERM-DEBT> 0
<OTHER-ITEMS-LIABILITIES> 1,886,398
<TOTAL-LIABILITIES> 1,886,398
<SENIOR-EQUITY> 123,968
<PAID-IN-CAPITAL-COMMON> 444,286,345
<SHARES-COMMON-STOCK> 12,396,827
<SHARES-COMMON-PRIOR> 8,505,676
<ACCUMULATED-NII-CURRENT> 48,823
<OVERDISTRIBUTION-NII> 0
<ACCUMULATED-NET-GAINS> (5,639,468)
<OVERDISTRIBUTION-GAINS> 0
<ACCUM-APPREC-OR-DEPREC> 52,146,729
<NET-ASSETS> 490,966,397
<DIVIDEND-INCOME> 2,688,677
<INTEREST-INCOME> 558,363
<OTHER-INCOME> 0
<EXPENSES-NET> 788,906
<NET-INVESTMENT-INCOME> 2,458,134
<REALIZED-GAINS-CURRENT> (1,779,521)
<APPREC-INCREASE-CURRENT> (18,841,125)
<NET-CHANGE-FROM-OPS> (18,162,512)
<EQUALIZATION> 0
<DISTRIBUTIONS-OF-INCOME> (294,085)
<DISTRIBUTIONS-OF-GAINS> 0
<DISTRIBUTIONS-OTHER> 0
<NUMBER-OF-SHARES-SOLD> 3,414,060
<NUMBER-OF-SHARES-REDEEMED> (2,577,562)
<SHARES-REINVESTED> 48,618
<NET-CHANGE-IN-ASSETS> 23,501,344
<ACCUMULATED-NII-PRIOR> 323,966
<ACCUMULATED-GAINS-PRIOR> 651,108
<OVERDISTRIB-NII-PRIOR> 0
<OVERDIST-NET-GAINS-PRIOR> 0
<GROSS-ADVISORY-FEES> 787,757
<INTEREST-EXPENSE> 0
<GROSS-EXPENSE> 788,906
<AVERAGE-NET-ASSETS> 69,777,815
<PER-SHARE-NAV-BEGIN> 5.99
<PER-SHARE-NII> 0.02
<PER-SHARE-GAIN-APPREC> (0.26)
<PER-SHARE-DIVIDEND> (0.02)
<PER-SHARE-DISTRIBUTIONS> 0.00
<RETURNS-OF-CAPITAL> 0.00
<PER-SHARE-NAV-END> 5.73
<EXPENSE-RATIO> 0.49
</TABLE>
