Editing Mercer County, New Jersey (section)

==Demographics==
{{US Census population
|1840= 21502
|1850= 27992
|1860= 37419
|1870= 46386
|1880= 58061
|1890= 79978
|1900= 95365
|1910=125657
|1920=159881
|1930=187143
|1940=197318
|1950=229781
|1960=266392
|1970=304116
|1980=307863
|1990=325824
|2000=350761
|2010=366513
|2020=387340
| estyear=2024
| estimate=392138
| estref=<ref name=Census2020/><ref name=PopEst>[https://www2.census.gov/programs-surveys/popest/tables/2020-2024/counties/totals/co-est2024-pop-34.xlsx Annual Estimates of the Resident Population for Counties in New Jersey: April 1, 2020 to July 1, 2024], [[United States Census Bureau]], released March 2025. Accessed March 26, 2025.</ref>
|footnote=Historical sources: 1790–1990<ref>Forstall, Richard L. [https://books.google.com/books?id=sezaSI_LPA8C&pg=PA108 ''Population of states and counties of the United States: 1790 to 1990 from the Twenty-one Decennial Censuses''], pp. 108-109. [[United States Census Bureau]], March 1996. {{ISBN|9780934213486}}. Accessed October 3, 2013.</ref><br />1970-2010<ref name=CPH232>[https://www.census.gov/prod/cen2010/cph-2-32.pdf#page=32 ''New Jersey: 2010 - Population and Housing Unit Counts; 2010 Census of Population and Housing''] {{webarchive|url=https://web.archive.org/web/20130723055400/http://www.census.gov/prod/cen2010/cph-2-32.pdf |archive-url=https://web.archive.org/web/20121019110730/http://www.census.gov/prod/cen2010/cph-2-32.pdf |archive-date=October 19, 2012 |url-status=live |date=July 23, 2013 }}, p. 6, CPH-2-32. [[United States Census Bureau]], August 2012. Accessed August 29, 2016.</ref> 2010-2019<ref name=Census2010>[https://archive.today/20200212095535/http://factfinder.census.gov/bkmk/table/1.0/en/DEC/10_DP/DPDP1/0500000US34021 DP1 - Profile of General Population and Housing Characteristics: 2010 Demographic Profile Data for Mercer County, New Jersey], [[United States Census Bureau]]. Accessed March 25, 2016.</ref> 2020<ref name=Census2020>[https://www.census.gov/quickfacts/mercercountynewjersey QuickFacts Mercer County, New Jersey], [[United States Census Bureau]]. Accessed March 26, 2025.</ref><ref name=LWD2020>[https://www.nj.gov/labor/labormarketinformation/assets/PDFs/census/2020/2020%20pl94%20Tables/2020_Mun/MCD%200_All.pdf Total Population: Census 2010 - Census 2020 New Jersey Municipalities], [[New Jersey Department of Labor and Workforce Development]]. Accessed December 1, 2022.</ref>
}}

===2020 census===
As of the [[2020 United States census]], Mercer County has a population of 387,340, making it the 12th most populous county in the state. The racial makeup of the county is quite diverse with 62.3% of the population identifying as white (and 46.7% as non-Hispanic whites), 21.6% of the population being black/African American, and 12.6% of the county's population identifying as Asian. 19.4% of Mercer County is Hispanic/Latino, 0.9% of the population is American Native/Alaskan Native/Native Hawaiian/Pacific Islander, and 2.6% identify as two or more races.<ref name=Census2020/>

5.4% of Mercer County is under the age of 5, while 21.2% are under the age of 18, and 16.0% are over the age of 65. The female population of the county stands at 50.8%, which is in line with the state as a whole.<ref name=Census2020/>

There are 150,657 housing units in Mercer County, with 63.5% of them being owned by the occupiers. There are 131,440 households with an average of 2.67 persons per household.<ref name=Census2020/>

===2010 census===
The [[2010 United States census]] counted 366,513 people, 133,155 households, and 89,480 families in the county. The [[population density]] was 1,632.2 per square mile (630.2/km<sup>2</sup>). There were 143,169 housing units at an average density of 637.6 per square mile (246.2/km<sup>2</sup>). The racial makeup was 61.39% (225,011) [[White (U.S. census)|White]], 20.28% (74,318) [[Black (U.S. census)|Black or African American]], 0.33% (1,194) [[Native American (U.S. census)|Native American]], 8.94% (32,752) [[Asian (U.S. census)|Asian]], 0.08% (295) [[Pacific Islander (U.S. census)|Pacific Islander]], 6.24% (22,856) from [[Race and ethnicity in the United States census#Race|other races]], and 2.75% (10,087) from two or more races. [[Hispanic (U.S. census)|Hispanic or Latino]] of any race were 15.09% (55,318) of the population.<ref name=Census2010/> 

Of the 133,155 households, 31.4% had children under the age of 18; 48.2% were married couples living together; 14.2% had a female householder with no husband present and 32.8% were non-families. Of all households, 26.9% were made up of individuals and 10.1% had someone living alone who was 65 years of age or older. The average household size was 2.61 and the average family size was 3.16.<ref name=Census2010/> 

22.6% of the population were under the age of 18, 10.9% from 18 to 24, 26.9% from 25 to 44, 26.9% from 45 to 64, and 12.6% who were 65 years of age or older. The median age was 37.8 years. For every 100 females, the population had 95.5 males. For every 100 females ages 18 and older there were 93 males.<ref name=Census2010/>