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Annual Total Returns - Fidelity Flex Inflation-Protected Bond Index Fund [BarChart] - 12.31 Fidelity Flex Inflation-Protected Bond Index Fund PRO-09 - Fidelity Flex Inflation-Protected Bond Index Fund
Mar. 01, 2022
Bar Chart Table:  
Annual Return, Inception Date Mar. 09, 2017
Fidelity Flex Inflation-Protected Bond Index Fund  
Bar Chart Table:  
Annual Return 2018 (1.35%)
Annual Return 2019 8.38%
Annual Return 2020 10.99%
Annual Return 2021 5.92%