Normally investing at least 80% of assets in municipal securities whose interest is exempt from federal income tax (but may be subject to the federal alternative minimum tax). Normally investing at least 80% of assets in securities included in the Fidelity Systematic U.S. Municipal Bond IndexSM, which aims to increase exposure to municipal bonds with higher risk-adjusted performance and liquidity characteristics relative to traditional market-capitalization weighted U.S. investment grade municipal bond indices. The Fidelity Systematic U.S. Municipal Bond Index SM is constructed using Fidelity's rules-based proprietary index methodology. The universe of securities includes U.S. dollar-denominated investment-grade tax-exempt debt publicly issued in the domestic market by U.S. states and territories, and their political subdivisions, that meet specific criteria such as issue size, deal size and maturity. Mandatory put or mandatory tender securities, as well as original issue zero-coupon bonds, are included in the universe. Floating rate bonds, derivatives, secondarily insured securities, Rule 144A securities, securities in legal default, securities issued under the municipal liquidity facility, or a municipal commercial paper program, and limited offering securities are excluded from the universe. Index constituents are not market capitalization weighted; instead each constituent's weight is determined by its characteristics such as credit quality, issue size, and maturity - aiming for higher risk-adjusted performance at the index level. Additionally, exposure is balanced across maturity buckets to ensure the index's overall duration is similar to traditional indices. Using statistical sampling techniques based on duration, maturity, interest rate sensitivity, security structure, and credit quality to attempt to replicate the returns of the Fidelity Systematic U.S. Municipal Bond IndexSM using a smaller number of securities.