Clay County is a county located in the U.S. state of Illinois. As of the 2010 census, the population was 13,815. Its county seat is Louisville. In 1950, the U.S. Census Bureau placed the mean center of U.S. population in Clay County.
In recent years, average temperatures in the county seat of Louisville have ranged from a low of in January to a high of in July, although a record low of was recorded in January 1904 and a record high of was recorded in July 1936. Average monthly precipitation ranged from in February to in June.
Demographics
As of the 2010 United States Census, there were 13,815 people, 5,697 households, and 3,790 families residing in the county. The population density was. There were 6,404 housing units at an average density of. The racial makeup of the county was 97.7% white, 0.5% Asian, 0.3% black or African American, 0.2% American Indian, 0.5% from other races, and 0.8% from two or more races. Those of Hispanic or Latino origin made up 1.1% of the population. In terms of ancestry, 21.7% were German, 14.6% were American, 12.6% were Irish, and 8.6% were English. Of the 5,697 households, 29.5% had children under the age of 18 living with them, 52.1% were married couplesliving together, 9.4% had a female householder with no husband present, 33.5% were non-families, and 28.9% of all households were made up of individuals. The average household size was 2.37 and the average family size was 2.89. The median age was 42.2 years. The median income for a household in the county was $38,016 and the median income for a family was $48,659. Males had a median income of $38,191 versus $27,347 for females. The per capita income for the county was $20,802. About 11.2% of families and 16.3% of the population were below the poverty line, including 21.4% of those under age 18 and 14.7% of those age 65 or over.
As part of Upper Southern-leaning Southern Illinois, Clay County is powerfully Republican. No Democratic presidential nominee has won a majority in Clay County since Lyndon Johnson’s 1964 landslide, and typically for the region recent presidential elections have seen dramatic declines in Democratic support due to disagreement with liberal positions on social issues.
