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(CNSNews.com) - Nine of the 20 richest counties in the United States—when measured by median household income—are suburbs of Washington, D.C., according to data released today by the Census Bureau.

In fact, two counties in the Northern Virginia suburbs of Washington, D.C., are richer than the two California counties that constitute Silicon Valley.

In 2018, according to the Census Bureau’s new Small Area Income and Poverty Estimates, Loudoun County, Va., was the nation’s richest county with a median household income of $140,382.

Falls Church City, Va., which the Census Bureau counts as a county because it is an independent city, ranked as the nation’s second richest county with a median household income of $137,551.

Behind Loudoun and Falls Church, the third richest county in the country was Santa Clara, Calif. ($125,933), which is the heart of Silicon Valley. San Mateo County, Calif. ($122,930), which sits between Santa Clara and San Francisco counties and is also considered part of Silicon Valley, ranked sixth.

In fact, other than the Washington, D.C., area, only two areas in the country had multiple counties that ranked among the Top 20 richest counties. These were the San Francisco Bay Area, which had four counties in the Top 20; and the New York City area, which also had four counties in the Top 20.

The only three counties that made the Top 20 that were not near Washington, San Francisco or New York were Los Alamos County, N.M. ($124,947), which ranked fourth; Douglas County, Colo. ($120,670), which ranked ninth; and Williamson County, Tenn. ($115,930), which ranked twelfth.

Los Alamos County, N.M. is home to the federal government’s Los Alamos National Laboratory, which is part of the U.S. Department of Energy. Douglas County, Colo., is south of Denver. Williamson County is south of Nashville.

In addition to Loudoun and Falls Church, the other seven counties in the Washington, D.C. area that ranked in the Top Twenty included: Fairfax County, Va. ($122,035), which ranked seventh; Arlington County, Va. ($120,950), which ranked eighth; Howard County, Md. ($116,719), which ranked eleventh; Stafford County, Va. ($108,421), which ranked seventeenth; Montgomery County, Md. ($107,758), which ranked eighteenth; Calvert County, Md. ($$106,270), which ranked nineteenth; and Prince William County, Va. ($106,200).

The four San Francisco-area counties that ranked in the Top 20 included: Santa Clara County, Calif. ($125,933), which ranked third; Marin County, Calif. ($122,933), which ranked fifth; San Mateo County, Calif. ($122,930), which ranked sixth; and San Francisco County ($110,610), which ranked sixteenth.

The four New York-area counties that ranked in the Top 20 included: Somerset County, N.J. ($119.731), which ranked tenth; Nassau County, N.Y. ($115,301), which ranked thirteenth; Morris County, N.J. ($112,396), which ranked fourteenth; and Hunterdon County, N.J. ($112,335), which ranked fifteenth.

The median household income nationwide in 2018, according to the Census Bureau, was $61,937.









