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Annual Total Returns - Fidelity Series Inflation-Protected Bond Index Fund [BarChart] - 12.31 Fidelity Series InflationProtected Bond Index Fund Series PRO-10 - Fidelity Series Inflation-Protected Bond Index Fund - Fidelity Series Inflation-Protected Bond Index Fund
Mar. 01, 2022
Bar Chart Table:  
Annual Return 2012 4.77%
Annual Return 2013 (5.77%)
Annual Return 2014 0.80%
Annual Return 2015 (0.92%)
Annual Return 2016 3.88%
Annual Return 2017 1.99%
Annual Return 2018 (0.42%)
Annual Return 2019 6.89%
Annual Return 2020 8.26%
Annual Return 2021 5.60%