46. Loudoun County, Virginia
> County median household income: $122,238
> State median household income: $63,907
> Pct. households in county making $200,000 or more: 19.8%
> 2013 county unemployment rate: 4.2%

With a median annual income of more than $122,000 over the five years through 2013, households located in Loudoun County were the wealthiest in both Virginia and the entire nation. On average, nearly one in five households reported an annual income of at least $200,000 over that period, also the highest proportion reviewed. Access to higher-paying jobs at the nation’s capital located nearby likely helped many residents earn high incomes. Income in Virginia, however, was perhaps the most unevenly distributed, as a typical household in Loudoun earned nearly $95,000 more than a typical household in Martinsville City, the state’s poorest area. This was the largest such gap considered.

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47. King County, Washington
> County median household income: $71,811
> State median household income: $59,478
> Pct. households in county making $200,000 or more: 9.1%
> 2013 county unemployment rate: 5.2%

Relatively high incomes usually provide people with the means to purchase homes and make other large investments. Yet, less than 60% of King County housing units were owned by their occupants. Only a handful of states’ wealthiest counties had homeownership rates lower than the comparable national rate of 64.9%. Many county residents are likely employed or living in Seattle, which makes up a large portion of the county. Higher paying jobs were also likely available in the city.

48. Jefferson County, West Virginia
> County median household income: $65,304
> State median household income: $41,043
> Pct. households in county making $200,000 or more: 4.5%
> 2013 county unemployment rate: 4.6%

Households in West Virginia had an annual median income of just over $41,000 over the five years through 2013, nearly the lowest of all states. Jefferson County residents were among the wealthiest in the state, with households earning $65,304 annually over that period. Residents were not especially well educated compared with those in other states’ richest counties. Less than 28% of adults in the area had at least a bachelor’s degree between 2009 and 2013, lower than the national figure and one of the lowest reviewed.

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49. Waukesha County, Wisconsin
> County median household income: $75,850
> State median household income: $52,413
> Pct. households in county making $200,000 or more: 7.6%
> 2013 county unemployment rate: 5.9%

Relatively high incomes in Waukesha County contributed to residents having one of the nation’s best health insurance coverage rates, as well as a relatively low poverty rate. Less than 5% of adults in the area did not have health insurance, and 5.4% of residents lived in poverty over the five years through 2013, both among the lowest rates nationwide.

50. Campbell County, Wyoming
> County median household income: $79,488
> State median household income: $57,406
> Pct. households in county making $200,000 or more: 4.4%
> 2013 county unemployment rate: 3.9%

Households in Campbell County had an annual median income of nearly $80,000 over the five years through 2013, the highest in the state as well as among the higher figures nationwide. However, residents were not especially well educated. Less than 19% of adults had at least a bachelor’s degree over that period, one of only a few figures reviewed that did not exceed the comparable national figure of 28.8%. The high incomes in Campbell may be due to the sizable growth rates in recent years of the state’s oil industry, which has also likely resulted in an unemployment rate of less than 4%.

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