Decatur County, Iowa

Major highways

• Interstate 35
• U.S. Highway 69
• Iowa Highway 2

Transit

• Jefferson Lines

Adjacent counties

• Clarke County (north)
• Wayne County (east)
• Mercer County, Missouri (southeast)
• Harrison County, Missouri (southwest)
• Ringgold County (west)

2020 census

As of the 2020 census, the county had a population of 7,645, which produced a population density of 14.3/sq mi (5.5/km²). The median age was 39.5 years. 23.2% of residents were under the age of 18 and 21.0% of residents were 65 years of age or older. For every 100 females there were 100.2 males, and for every 100 females age 18 and over there were 98.1 males age 18 and over.^[14]

96.44% of residents reported being of one race. The racial makeup of the county was 92.6% White, 1.4% Black or African American, 0.3% American Indian and Alaska Native, 0.5% Asian, 0.3% Native Hawaiian and Pacific Islander, 1.3% from some other race, and 3.6% from two or more races. Hispanic or Latino residents of any race comprised 2.8% of the population.^[15]

<0.1% of residents lived in urban areas, while 100.0% lived in rural areas.^[17]

There were 2,986 households in the county, of which 27.5% had children under the age of 18 living in them. Of all households, 50.5% were married-couple households, 20.7% were households with a male householder and no spouse or partner present, and 23.6% were households with a female householder and no spouse or partner present. About 30.8% of all households were made up of individuals and 14.3% had someone living alone who was 65 years of age or older.^[14]

There were 3,653 housing units, of which 2,986 were occupied, leaving an 18.3% vacancy rate. Among occupied housing units, 72.5% were owner-occupied and 27.5% were renter-occupied. The homeowner vacancy rate was 2.7% and the rental vacancy rate was 13.4%.^[14]

2010 census

The 2010 census recorded a population of 8,457 in the county, with a population density of 15.9/sq mi (6.1/km²). There were 3,834 housing units, of which 3,223 were occupied.^[18]

2000 census

At the 2000 census,^[19] there were 8,689 people, 3,337 households and 2,149 families residing in the county. The population density was 16 per square mile (6.2/km²). There were 3,833 housing units at an average density of 7 per square mile (2.7/km²). The racial makeup of the county was 96.46% White, 0.98% Black or African American, 0.24% Native American, 0.63% Asian, 0.12% Pacific Islander, 0.46% from other races, and 1.12% from two or more races. 1.70% of the population were Hispanic or Latino of any race.

There were 3,337 households, of which 28.00% had children under the age of 18 living with them, 54.30% were married couples living together, 7.20% had a female householder with no husband present, and 35.60% were non-families. 30.30% of all households were made up of individuals, and 15.50% had someone living alone who was 65 years of age or older. The average household size was 2.37 and the average family size was 2.96.

23.00% of the population were under the age of 18, 16.30% from 18 to 24, 21.60% from 25 to 44, 21.50% from 45 to 64, and 17.70% who were 65 years of age or older. The median age was 36 years. For every 100 females there were 95.70 males. For every 100 females age 18 and over, there were 91.90 males.

The median household income was $27,343 and the median family income was $34,831. Males had a median income of $25,569 compared with $19,309 for females. The per capita income for the county was $14,209. About 10.90% of families and 15.50% of the population were below the poverty line, including 15.60% of those under age 18 and 13.70% of those age 65 or over.

Decatur County is considered to be the poorest in Iowa, reporting that almost 20% of its residents live in poverty.^[20]

Cities

Townships

Decatur County is divided into these townships:

Population ranking

The population ranking of the following table is based on the 2020 census of Decatur County.^[3]

† county seat