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Annual Total Returns - Fidelity® SAI U.S. Momentum Index Fund [BarChart] - 07.31 Fidelity SAI U.S. Momentum Index Fund PRO-07 - Fidelity® SAI U.S. Momentum Index Fund
Sep. 29, 2020
Bar Chart Table:  
Annual Return, Inception Date Feb. 09, 2017
Fidelity SAI U.S. Momentum Index Fund - Default  
Bar Chart Table:  
Annual Return 2018 (1.40%)
Annual Return 2019 24.16%