page_title: Washington County, Iowa
section_title: 2000 census
hierarchical_section_title: Washington County, Iowa / Demographics / 2000 census
context_page_description: Washington County is a county located in the U.S. state of Iowa. As of the 2010 census, the population was 21,704. The county seat is Washington.
  Washington County is included in the Iowa City Metropolitan Statistical Area.
context_section_description: As of the census of 2000, there were 20,670 people, 8,056 households, and 5,631 families residing in the county. The population density was 36 inhabitants per square mile (14/km²). There were 8,543 housing units at an average density of 15 per square mile (5.8/km²). The racial makeup of the county was 97.04% White, 0.29% Black or African American, 0.19% Native American, 0.25% Asian, 0.03% Pacific Islander, 1.51% from other races, and 0.68% from two or more races. 2.73% of the population were Hispanic or Latino of any race.
  There were 8,056 households, out of which 31.40% had children under the age of 18 living with them, 60.30% were married couples living together, 6.70% had a female householder with no husband present, and 30.10% were non-families. 26.40% of all households were made up of individuals, and 12.50% had someone living alone who was 65 years of age or older. The average household size was 2.50 and the average family size was 3.04.
  In the county, the population was spread out, with 26.10% under the age of 18, 7.00% from 18 to 24, 26.80% from 25 to 44, 22.30% from 45 to 64, and 17.90% who were 65 years of age or older. The median age was 39 years. For every 100 females, there were 93.00 males. For every 100 females age 18 and over, there were 90.10 males.
  The median income for a household in the county was $39,103, and the median income for a family was $45,636. Males had a median income of $29,592 versus $22,818 for females. The per capita income for the county was $18,221. About 5.10% of families and 7.60% of the population were below the poverty line, including 10.30% of those under age 18 and 7.30% of those age 65 or over.
caption: 2000 Census Age Pyramid for Washington County