Strategy. Normally investing at least 80% of assets in common stocks included in the Fidelity U.S. Extended Investable Market IndexSM. The Fidelity U.S. Extended Investable Market Index SM is a float-adjusted market capitalization-weighted index designed to reflect the performance of U.S. mid- and small-cap stocks. Effective December 11, 2025, derivative instruments that provide investment exposure to the investments above or exposure to one or more market risk factors associated with such investments are included in the fund's 80% policy, consistent with the fund's investment policies and limitations with respect to investments in derivatives. Using statistical sampling techniques based on such factors as capitalization, industry exposures, dividend yield, price -to-earnings (P/E) ratio, price -to-book (P/B) ratio, and earnings growth to attempt to … Show more… Normally investing at least 80% of assets in common stocks included in the Fidelity U.S. Extended Investable Market IndexSM. The Fidelity U.S. Extended Investable Market Index SM is a float-adjusted market capitalization-weighted index designed to reflect the performance of U.S. mid- and small-cap stocks. Effective December 11, 2025, derivative instruments that provide investment exposure to the investments above or exposure to one or more market risk factors associated with such investments are included in the fund's 80% policy, consistent with the fund's investment policies and limitations with respect to investments in derivatives. Using statistical sampling techniques based on such factors as capitalization, industry exposures, dividend yield, price -to-earnings (P/E) ratio, price -to-book (P/B) ratio, and earnings growth to attempt to replicate the returns of the Fidelity U.S. Extended Investable Market Index?. Lending securities to earn income for the fund. Show less