the Washington National Cathedral, the Basilica of the National Shrine of the Immaculate Conception, which comprises the largest Catholic church building in the United States, and the Islamic Center of Washington, which was the largest mosque in the Western Hemisphere when opened in 1957. St. John's Episcopal Church, located off Lafayette Square, has held services for every U.S. president since James Madison. The Sixth & I Historic Synagogue, built in 1908, is a synagogue located in the Chinatown section of the city. The Washington D.C. Temple is a large Mormon temple located just outside the city in Kensington, Maryland. Viewable from the Capital Beltway, the Washington, D.C. Mormon Temple is the tallest Mormon temple in existence and the third-largest by square footgage. Economy As of 2020, the Washington metropolitan area, including Washington, D.C. and parts of Northern Virginia, Maryland, and West Virginia, was the nation's fourth-largest metropolitan economy as measured by gross metropolitan product (GMP). Its growing and diversified economy has an increasing percentage of professional and business service jobs in addition to more traditional jobs rooted in tourism, entertainment, and government. Between 2009 and 2016, gross domestic product per capita in Washington, D.C. consistently ranked at the very top among U.S. states. In 2016, at $160,472, its GDP per capita was almost three times greater than that of Massachusetts, which was ranked second in the nation. , the metropolitan statistical area's unemployment rate was 3.1%, ranking 171 out of the 389 metropolitan areas as defined by the U.S. Bureau of Economic Analysis. The District of Columbia itself had an unemployment rate of 4.6% during the same time period. In 2019, Washington, D.C. had the highest median household income in the U.S. at $92,266. Federal government As of July 2022, 25% of people employed in Washington, D.C. were employed by the federal government. The vast majority of these government employees serve in various executive branch departments, agencies, and institutions, and only a small percentage serve as temporary staff for presidents, Congress members, or in the federal judiciary. Many of the region's residents work for companies and organizations that sign contracts with the federal government or work on issues directly related to the work of the federal government, including law firms, defense contractors, civilian contractors, nonprofit organizations, lobbying firms, trade unions, industry trade groups, and professional associations, many of which have their headquarters in or near Washington, D.C. in order to