Jacksonville, Illinois

==Demographics==
{{US Census population
|1850= 2745
|1860= 5528
|1870= 9203
|1880= 10927
|1890= 12935
|1900= 15078
|1910= 15326
|1920= 15713
|1930= 17747
|1940= 19844
|1950= 20387
|1960= 21690
|1970= 20553
|1980= 20284
|1990= 19324
|2000= 18940
|2010= 19446
|2020= 17616
|footnote=U.S. Decennial Census<ref name="DecennialCensus">{{cite web|url=https://www.census.gov/programs-surveys/decennial-census.html|title=Census of Population and Housing|publisher=Census.gov|access-date=June 4, 2015}}</ref>
}}
As of the census<ref>{{cite web|url=https://www.census.gov |publisher=[[United States Census Bureau]] |title=U.S. Census website |access-date=January 25, 2015 }}</ref> of 2010, there were 19,446 people, 7,357 households, and 4,174 families residing in the city. The population density was {{convert|1,905|PD/sqmi|PD/km2|sp=us|adj=off}}. There were 8,162 housing units at an average density of {{convert|805.5|/sqmi|/km2|sp=us|adj=off}}. The racial makeup of the city was 85.3% [[White (U.S. Census)|White]], 10.2% [[African American (U.S. Census)|African American]], 0.3% [[Native American (U.S. Census)|Native American]], 0.7% [[Asian (U.S. Census)|Asian]], 1.1% from [[Race (United States Census)|other races]], and 2.4% from two or more races. [[Hispanic (U.S. Census)|Hispanic]] or [[Latino (U.S. Census)|Latino]] of any race were 3% of the population.

There were 7,357 households, out of which 24.3% had children under the age of 18 living with them, 38.8% were married couples living together, 13.7% had a female householder with no husband present, and 43.3% were non-families. 36.3% of all households were made up of individuals, and 13.9% had someone living alone who was 65 years of age or older. The average household size was 2.23 and the average family size was 2.88.

In the city, the population was spread out, with 22.0% under the age of 18, 14.2% from 18 to 24, 25.1% from 25 to 44, 21.9% from 45 to 64, and 16.9% who were 65 years of age or older. The median age was 37 years. For every 100 females, there were 91.0 males. For every 100 females age 18 and over, there were 87.4 males.

The median income for a household in the city was $40,670, and the median income for a family was $56,343. Males had a median income of $42,409 versus $30,208 for females. The per capita income for the city was $21,245. About 11.9% of families and 18% of the population were below the poverty line, including 24.9% of those under age 18 and 11.8% of those age 65 or over.