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Annual Total Returns - Fidelity® SAI Small-Mid Cap 500 Index Fund [BarChart] - 07.31 Fidelity SAI Small-Mid Cap 500 Index Fund PRO-08 - Fidelity® SAI Small-Mid Cap 500 Index Fund
Sep. 29, 2020
Bar Chart Table:  
Annual Return, Inception Date Aug. 12, 2015
Fidelity SAI Small-Mid Cap 500 Index Fund-Default  
Bar Chart Table:  
Annual Return 2016 14.62%
Annual Return 2017 18.40%
Annual Return 2018 (9.25%)
Annual Return 2019 29.53%