Strategy. Under normal market conditions, the fund invests at least 80% of its assets, exclusive of collateral held from securities lending, in the component securities of the underlying index. The American Century Quality Diversified International Equity Index (Index) is a rules-based index maintained by American Century Investment Management, Inc. (the index provider). The Index is designed to select securities with attractive quality, growth and valuation fundamentals. The universe of the Index is comprised of large- and mid-capitalization equity securities of global issuers outside of the United States. The Index focuses on securities of issuers from developed economies. To construct the Index, the index provider first screens the underlying universe, selecting securities with higher profitability, return on assets, return on equity, and … Show more… Under normal market conditions, the fund invests at least 80% of its assets, exclusive of collateral held from securities lending, in the component securities of the underlying index. The American Century Quality Diversified International Equity Index (Index) is a rules-based index maintained by American Century Investment Management, Inc. (the index provider). The Index is designed to select securities with attractive quality, growth and valuation fundamentals. The universe of the Index is comprised of large- and mid-capitalization equity securities of global issuers outside of the United States. The Index focuses on securities of issuers from developed economies. To construct the Index, the index provider first screens the underlying universe, selecting securities with higher profitability, return on assets, return on equity, and gross margins while considering earnings, leverage and momentum. The index provider next determines a growth score and a value score for each selected security. The growth scores are based on sales, earnings, profitability, cash flows and momentum. The value scores are based on value, earnings yield, dividend yield, and cash flow metrics. The index provider categorizes securities into sub-portfolios based on country and attribute, and then weights securities in each sub-portfolio based on combined growth and value scores. Though component securities of the Index may change from time to time, the index typically consists of 300500 securities and, as of September 30, 2025, the market capitalization range of the Index was approximately $4.6 billion and larger. For purposes of investing at least 80% of its assets in securities included in the Index, the fund may invest in depositary receipts representing securities included in the Index or securities representing depositary receipts included in the Index. The Index and the fund are rebalanced monthly and reconstituted quarterly. The fund may use a representative sampling strategy with respect to its Index instead of a replication strategy. For example, the fund may use such strategy when there are practical difficulties or substantial costs involved in compiling a portfolio of securities to follow the Index or, in certain instances, when a component security becomes temporarily illiquid, unavailable or less liquid. To the extent the fund uses representative sampling, the advisor invests in what it believes to be a representative sample of the component securities in the Index using quantitative analytical procedures to give the funds portfolio an investment profile similar to that of its Index. The fund also may realize savings in transaction costs or other efficiencies by investing up to 20% of its assets in securities or instruments not included in the Index but which the advisor believes will help the fund track the Index. When deciding whether to buy or sell a security, and how and when to implement a trade, the portfolio managers may consider the expected implementation costs and tax consequences of the trade in an attempt to gain trading efficiencies, avoid unnecessary risk, minimize tax impact, and/or enhance fund performance. In addition, the fund may use futures contracts to invest cash balances, simulate investments in the Index, facilitate trading or minimize transaction costs. The portfolio managers may also use futures contracts to seek to reduce the funds tracking error relative to the Index. The fund may concentrate its investments ( i.e. , hold 25% or more of its net assets) in a particular industry or group of industries to the extent that the Index is concentrated. If the Index has high portfolio turnover, the fund may also have high portfolio turnover. This may cause higher transaction costs and may affect performance. It may also result in the realization and distribution of capital gains. Show less