Editing Decatur, Illinois (section)

===2010 census===
As of the [[2020 United States census|2010 census]], there were 76,122 people, 32,344 households, and 18,991 families residing in the city.<ref name=":0">{{cite web|url=https://factfinder.census.gov/bkmk/table/1.0/en/DEC/10_DP/DPDP1/1600000US1718823|title=Decatur city, Illinois|website=Profile of General Population and Housing Characteristics: 2010|publisher=US Census Bureau|access-date=October 11, 2019|archive-url=https://archive.today/20200213095017/https://factfinder.census.gov/bkmk/table/1.0/en/DEC/10_DP/DPDP1/1600000US1718823|archive-date=February 13, 2020|url-status=dead}}</ref> The population density was {{convert|1,800.9|PD/sqmi|PD/km2|adj=off}}. There were 36,134 housing units at an average density of {{convert|854.8|/sqmi|/km2|adj=off}}. The racial makeup of the city was 71.6% [[Race and ethnicity in the United States Census|White]], 23.3% [[Race and ethnicity in the United States Census|African American]], 0.2% [[Race and ethnicity in the United States Census|Native American]], 0.9% [[Race and ethnicity in the United States Census|Asian]], 0.9% from [[Race and ethnicity in the United States Census|other races]], and 3.1% from two or more races.<ref name=":0" /> [[Race and ethnicity in the United States Census|Hispanic]] or [[Race and ethnicity in the United States Census|Latino]] people of any race were 2.2% of the population.<ref name=":0" />

There were 32,344 households, out of which 24.2% had children under the age of 18 living with them, 37.4% were married couples living together, 16.9% had a female household with no husband present, and 41.3% were non-families. 35.2% of all households were made up of individuals, and 13.2% 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 2.86.

In the city, the population was spread out, with 22.1% under the age of 18, 10.8% from ages 18 to 24, 23.4% from ages 25 to 44, 26.8% from ages 45 to 64, and 16.9% who were 65 years of age or older. The median age was 39.1 years. For every 100 females, there were 88.0 males. For every 100 females aged 18 and over, there were 85.3 males.

As of 2017, the median income for a household in the city was $41,977, and the median income for a family was $55,086. Males had a median income of $35,418 versus $34,389 for females. The per capita income for the city was $25,042. About 22% of the population is below the [[Poverty threshold|poverty line]], including 35% of those under age 18 and 10% of those age 65 or over.

Decatur is listed by the [[United States Census Bureau]] as number three in "The 15 Fastest-Declining Large Cities" which showed a 7.1% population loss of (−5,376) from 2010 to 2019.<ref name=":2">{{Cite web|title=Decatur city, Illinois (Data in Table 2)|url=https://www.census.gov/newsroom/press-releases/2020/south-west-fastest-growing.html|date=May 21, 2020|website=Southern and Western Regions Experienced Rapid Growth This Decade|access-date=May 22, 2020}}<!--note: this website could not be archived by either archive.org nor archive.is--></ref> The ''Chicago Tribune'' says: "in 1980, Decatur's population was at a high of 94,000. Now it is 71,000."<ref>{{cite news|work=Chicago Tribune|date=June 8, 2020|title=Midwestern cities continue to lose population. Two of the fastest-shrinking are in Illinois.|url=https://www.chicagotribune.com/news/breaking/ct-census-illinois-cities-population-loss-20200608-elh5s7pq7vcjriqnlii6hyaiea-story.html}}</ref>