Other pages about the topic: County data

Educational attainment (mapped by county)

Percent high school graduates

Population Age 25 and Above, 2019

Whitman (95.5%), San Juan (95.9%) and Island (95.3%) County had the highest percentages of high school graduates.

Adams (66.9%), Yakima (73.7%) and Franklin (75.0%) County had the lowest percentages of high school graduates.

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Languages spoken at home (mapped by county)

Percent in households where English is spoken less than "very well"

Population Age 5 and Above, 2019

The smallest share of population where English was spoken less than "Very Well" was in Pend Oreille County at 0.5%. The highest share was in Adams County where 29.0% of persons were in this category.

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Population by age, mapped by county

Median Age, 2020

In 2010, the median age of persons living in Washington state was 37.3 years. In 2020 the median age had increased to 38.5 years.

Jefferson County had the highest median age in 2010 at 53.9 years. By 2020, the median age in Jefferson County had reached 59.5 years.

Hispanic population as a percent of total population


In 2020, the highest percentages of Hispanic residents were found in central Washington with Adams (69.2%), Franklin (55.9%), and Yakima (51.9%) counties posting the highest shares.

Poverty rate for single-parent families headed by a female householder (mapped by county)


Klickitat County had the highest percentage of single mother families in poverty at 63.3%.

The lowest poverty rates for families headed by single mothers was found in Asotin County at 19.0%.

Single-parent families as a percent of all families with children (mapped by county)


Ferry County had the highest percentage of single parent families with 44.9%.

Wahiakum County had the lowest share of single parent families, with 12.1%.

Population by county — census data (map)

Population, 2010


Population, 2000

Population Change, 2000–2010

Median household income estimates

Median Household Income Estimates by County: 1989 to 2020 and Projection for 2021