Data / Rankings / Population aged 18 to 64 / Counties in Illinois

Counties in Illinois by population aged 18 to 64

Brown County had the highest population aged 18 to 64 of 102 counties in 2016, at 69.2%. Jo Daviess County had the lowest, at 54.8%. The median was 59.1% and the figure for Illinois was 62.6%. Source: the U.S. Census Bureau.

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Highest69.2Brown County
Lowest54.8Jo Daviess County
Median59.1102 counties
Illinois62.6History

Map of counties, 2016

Adams County: 58.1 %Alexander County: 56.6 %Bond County: 63.6 %Boone County: 59.2 %Brown County: 69.2 %Bureau County: 57.5 %Calhoun County: 55.5 %Carroll County: 58.1 %Cass County: 59.3 %Champaign County: 69.2 %Christian County: 60.3 %Clark County: 57.8 %Clay County: 57.4 %Clinton County: 61.9 %Coles County: 64.3 %Cook County: 64.5 %Crawford County: 60.5 %Cumberland County: 58.4 %DeKalb County: 65.1 %De Witt County: 59.2 %Douglas County: 57 %DuPage County: 62.6 %Edgar County: 58 %Edwards County: 57.1 %Effingham County: 59.4 %Fayette County: 61.3 %Ford County: 57.4 %Franklin County: 57.8 %Fulton County: 59.7 %Gallatin County: 55.8 %Greene County: 58.5 %Grundy County: 60.7 %Hamilton County: 56.5 %Hancock County: 56.4 %Hardin County: 55.1 %Henderson County: 56.7 %Henry County: 57.3 %Iroquois County: 57 %Jackson County: 66.6 %Jasper County: 58.2 %Jefferson County: 59.2 %Jersey County: 59.9 %Jo Daviess County: 54.8 %Johnson County: 62.2 %Kane County: 61 %Kankakee County: 60.6 %Kendall County: 60.6 %Knox County: 60 %Lake County: 62.1 %LaSalle County: 60.3 %Lawrence County: 63.2 %Lee County: 61.7 %Livingston County: 59.6 %Logan County: 62.3 %McDonough County: 65 %McHenry County: 62.4 %McLean County: 65.4 %Macon County: 58.9 %Macoupin County: 59.1 %Madison County: 61.8 %Marion County: 57.7 %Marshall County: 57.2 %Mason County: 57.4 %Massac County: 56.8 %Menard County: 58.6 %Mercer County: 57 %Monroe County: 60.1 %Montgomery County: 60.2 %Morgan County: 61 %Moultrie County: 55.9 %Ogle County: 59.2 %Peoria County: 60.5 %Perry County: 62 %Piatt County: 58.2 %Pike County: 56.7 %Pope County: 56.6 %Pulaski County: 57.4 %Putnam County: 59.1 %Randolph County: 61.8 %Richland County: 57.4 %Rock Island County: 59.6 %St. Clair County: 61.5 %Saline County: 57.7 %Sangamon County: 60.8 %Schuyler County: 59.3 %Scott County: 58.8 %Shelby County: 57.2 %Stark County: 56.2 %Stephenson County: 56.8 %Tazewell County: 59 %Union County: 58.8 %Vermilion County: 58.1 %Wabash County: 58.2 %Warren County: 58.9 %Washington County: 59.5 %Wayne County: 56.2 %White County: 56.3 %Whiteside County: 57.6 %Will County: 61.8 %Williamson County: 59.5 %Winnebago County: 60.3 %Woodford County: 57.9 %
  • Under 57
  • 57 to 58
  • 58 to 59
  • 59 to 60
  • 60 to 62
  • 62 and over
%, 2016. Source: Invokely calculation with data from U.S. Census Bureau. Boundaries: U.S. Census Bureau cartographic boundary files.

Top 40 counties, 2016

Brown County: 69.2 %Brown County69.2Champaign County: 69.2 %Champaign County69.2Jackson County: 66.6 %Jackson County66.6McLean County: 65.4 %McLean County65.4DeKalb County: 65.1 %DeKalb County65.1McDonough County: 65 %McDonough County65Cook County: 64.5 %Cook County64.5Coles County: 64.3 %Coles County64.3Bond County: 63.6 %Bond County63.6Lawrence County: 63.2 %Lawrence County63.2DuPage County: 62.6 %DuPage County62.6McHenry County: 62.4 %McHenry County62.4Logan County: 62.3 %Logan County62.3Johnson County: 62.2 %Johnson County62.2Lake County: 62.1 %Lake County62.1Perry County: 62 %Perry County62Clinton County: 61.9 %Clinton County61.9Will County: 61.8 %Will County61.8Randolph County: 61.8 %Randolph County61.8Madison County: 61.8 %Madison County61.8Lee County: 61.7 %Lee County61.7St. Clair County: 61.5 %St. Clair County61.5Fayette County: 61.3 %Fayette County61.3Kane County: 61 %Kane County61Morgan County: 61 %Morgan County61Sangamon County: 60.8 %Sangamon County60.8Grundy County: 60.7 %Grundy County60.7Kendall County: 60.6 %Kendall County60.6Kankakee County: 60.6 %Kankakee County60.6Crawford County: 60.5 %Crawford County60.5Peoria County: 60.5 %Peoria County60.5Winnebago County: 60.3 %Winnebago County60.3LaSalle County: 60.3 %LaSalle County60.3Christian County: 60.3 %Christian County60.3Montgomery County: 60.2 %Montgomery County60.2Monroe County: 60.1 %Monroe County60.1Knox County: 60 %Knox County60Jersey County: 59.9 %Jersey County59.9Fulton County: 59.7 %Fulton County59.7Rock Island County: 59.6 %Rock Island County59.6Brown County: 69.2 %Brown County69.2Champaign County: 69.2 %Champaign County69.2Jackson County: 66.6 %Jackson County66.6McLean County: 65.4 %McLean County65.4DeKalb County: 65.1 %DeKalb County65.1McDonough County: 65 %McDonough County65Cook County: 64.5 %Cook County64.5Coles County: 64.3 %Coles County64.3Bond County: 63.6 %Bond County63.6Lawrence County: 63.2 %Lawrence County63.2DuPage County: 62.6 %DuPage County62.6McHenry County: 62.4 %McHenry County62.4Logan County: 62.3 %Logan County62.3Johnson County: 62.2 %Johnson County62.2Lake County: 62.1 %Lake County62.1Perry County: 62 %Perry County62Clinton County: 61.9 %Clinton County61.9Will County: 61.8 %Will County61.8Randolph County: 61.8 %Randolph County61.8Madison County: 61.8 %Madison County61.8Lee County: 61.7 %Lee County61.7St. Clair County: 61.5 %St. Clair County61.5Fayette County: 61.3 %Fayette County61.3Kane County: 61 %Kane County61Morgan County: 61 %Morgan County61Sangamon County: 60.8 %Sangamon County60.8Grundy County: 60.7 %Grundy County60.7Kendall County: 60.6 %Kendall County60.6Kankakee County: 60.6 %Kankakee County60.6Crawford County: 60.5 %Crawford County60.5Peoria County: 60.5 %Peoria County60.5Winnebago County: 60.3 %Winnebago County60.3LaSalle County: 60.3 %LaSalle County60.3Christian County: 60.3 %Christian County60.3Montgomery County: 60.2 %Montgomery County60.2Monroe County: 60.1 %Monroe County60.1Knox County: 60 %Knox County60Jersey County: 59.9 %Jersey County59.9Fulton County: 59.7 %Fulton County59.7Rock Island County: 59.6 %Rock Island County59.6
%. Source: Invokely calculation with data from U.S. Census Bureau. Retrieved 2026-10-12.

Full ranking

RankCounties2016 (%)Change on 2015
1Brown County69.2-0.9 pts
2Champaign County69.2-0.4 pts
3Jackson County66.6-1.1 pts
4McLean County65.4-0.4 pts
5DeKalb County65.1-0.5 pts
6McDonough County65-1.1 pts
7Cook County64.5-0.1 pts
8Coles County64.3-0.7 pts
9Bond County63.6-0.4 pts
10Lawrence County63.2-0.1 pts
11DuPage County62.6-0.3 pts
12McHenry County62.4-0.2 pts
13Logan County62.3-0.5 pts
14Johnson County62.2-1 pts
15Lake County62.1-0.2 pts
16Perry County62-0.4 pts
17Clinton County61.9-0.2 pts
18Will County61.8-0.1 pts
19Randolph County61.8-0.7 pts
20Madison County61.8-0.2 pts
21Lee County61.7-0.3 pts
22St. Clair County61.5-0.4 pts
23Fayette County61.3-0.3 pts
24Kane County61-0.1 pts
25Morgan County61+0.1 pts
26Sangamon County60.8-0.5 pts
27Grundy County60.7-0.2 pts
28Kendall County60.6-0.2 pts
29Kankakee County60.6-0.2 pts
30Crawford County60.5-0.3 pts
31Peoria County60.5-0.4 pts
32Winnebago County60.3-0.2 pts
33LaSalle County60.3-0.2 pts
34Christian County60.30 pts
35Montgomery County60.2-0.3 pts
36Monroe County60.1-0.5 pts
37Knox County60-0.5 pts
38Jersey County59.9-0.4 pts
39Fulton County59.7-0.5 pts
40Rock Island County59.6-0.3 pts
41Livingston County59.6-0.6 pts
42Williamson County59.5-0.3 pts
43Washington County59.5-0.8 pts
44Effingham County59.4-0.2 pts
45Cass County59.3-0.3 pts
46Schuyler County59.3-0.2 pts
47Ogle County59.2-0.3 pts
48Jefferson County59.2-0.8 pts
49De Witt County59.2-0.4 pts
50Boone County59.2-0.2 pts
51Macoupin County59.1-0.3 pts
52Putnam County59.1-0.5 pts
53Tazewell County59-0.4 pts
54Warren County58.9-0.5 pts
55Macon County58.9-0.5 pts
56Scott County58.8-0 pts
57Union County58.8-0.3 pts
58Menard County58.6-0.6 pts
59Greene County58.5-0.3 pts
60Cumberland County58.4-0.5 pts
61Piatt County58.2-0.5 pts
62Wabash County58.2-0.6 pts
63Jasper County58.2-0.4 pts
64Vermilion County58.1-0.4 pts
65Adams County58.1-0.4 pts
66Carroll County58.1-0.3 pts
67Edgar County58-0.1 pts
68Woodford County57.9-0.4 pts
69Clark County57.8-0.4 pts
70Franklin County57.8-0.3 pts
71Saline County57.7-0.3 pts
72Marion County57.7-0.3 pts
73Whiteside County57.6-0.3 pts
74Bureau County57.5-0.4 pts
75Mason County57.4-0.2 pts
76Ford County57.4-0 pts
77Clay County57.4-0.5 pts
78Richland County57.4-0.3 pts
79Pulaski County57.4-0.6 pts
80Henry County57.3-0.5 pts
81Marshall County57.2-0.7 pts
82Shelby County57.2-0.5 pts
83Edwards County57.1-0.5 pts
84Mercer County57-0.2 pts
85Iroquois County57-0.2 pts
86Douglas County57-0.3 pts
87Stephenson County56.8-0.5 pts
88Massac County56.8-0.6 pts
89Pike County56.7-0.2 pts
90Henderson County56.7-0.2 pts
91Pope County56.6-1 pts
92Alexander County56.6-0.3 pts
93Hamilton County56.5-0.5 pts
94Hancock County56.4-0.1 pts
95White County56.30 pts
96Wayne County56.2-0.5 pts
97Stark County56.2-0.1 pts
98Moultrie County55.9-0.3 pts
99Gallatin County55.8-0.8 pts
100Calhoun County55.5-0.5 pts
101Hardin County55.1-0.1 pts
102Jo Daviess County54.8-0.8 pts

Other periods

About this ranking

Residents aged 18 to 64 as a percentage of total population on 1 July. United States: Census Bureau county population estimates by age; states and the nation are sums of their counties.

Not comparable with working-age shares for ages 15 to 64 used in EU and World Bank statistics.

Every value in the ranking comes from the same publisher and the same period, so the counties are compared on one definition. Equal values share a rank.

How to cite

U.S. Census Bureau. Population Estimates Program, county population by age and sex: residents aged 18 to 64 as a percentage of the total on 1 July, 2010 to 2019 from the 2010 to 2020 intercensal file and 2020 onwards from the latest vintage; states and the nation summed from counties. https://www.census.gov/programs-surveys/popest/data/data-sets.html. Retrieved 2026-10-12.

Citation styles

The publisher is the author. Invokely is named only as the place the figures were read, where a style asks for it.

APA 7

U.S. Census Bureau. (2026). Population Estimates Program, county population by age and sex: residents aged 18 to 64 as a percentage of the total on 1 July, 2010 to 2019 from the 2010 to 2020 intercensal file and 2020 onwards from the latest vintage; states and the nation summed from counties (Counties in Illinois by population aged 18 to 64, 2016) [Data set]. Retrieved October 12, 2026, from https://www.census.gov/programs-surveys/popest/data/data-sets.html

MLA 9

Population Estimates Program, county population by age and sex: residents aged 18 to 64 as a percentage of the total on 1 July, 2010 to 2019 from the 2010 to 2020 intercensal file and 2020 onwards from the latest vintage; states and the nation summed from counties, Counties in Illinois by population aged 18 to 64, 2016. U.S. Census Bureau, 25 June 2026, https://www.census.gov/programs-surveys/popest/data/data-sets.html. Invokely, https://invokely.ai/rankings/population-18-64/illinois-counties?period=2016. Accessed 12 Oct. 2026.

Chicago (author-date)

U.S. Census Bureau. 2026. Population Estimates Program, county population by age and sex: residents aged 18 to 64 as a percentage of the total on 1 July, 2010 to 2019 from the 2010 to 2020 intercensal file and 2020 onwards from the latest vintage; states and the nation summed from counties. Counties in Illinois by population aged 18 to 64, 2016. Dataset. Accessed October 12, 2026. https://www.census.gov/programs-surveys/popest/data/data-sets.html. Also distributed by Invokely, https://invokely.ai/rankings/population-18-64/illinois-counties?period=2016.

Harvard

U.S. Census Bureau (2026) Population Estimates Program, county population by age and sex: residents aged 18 to 64 as a percentage of the total on 1 July, 2010 to 2019 from the 2010 to 2020 intercensal file and 2020 onwards from the latest vintage; states and the nation summed from counties, Counties in Illinois by population aged 18 to 64, 2016 [Dataset]. Available at: https://www.census.gov/programs-surveys/popest/data/data-sets.html, via Invokely: https://invokely.ai/rankings/population-18-64/illinois-counties?period=2016 (Accessed: 12 October 2026).

BibTeX
@misc{census_counties_in_illinois_by_2016,
  author = {{U.S. Census Bureau}},
  title = {{Population Estimates Program, county population by age and sex: residents aged 18 to 64 as a percentage of the total on 1 July, 2010 to 2019 from the 2010 to 2020 intercensal file and 2020 onwards from the latest vintage; states and the nation summed from counties: Counties in Illinois by population aged 18 to 64, 2016}},
  year = {2026},
  howpublished = {Data set},
  url = {https://www.census.gov/programs-surveys/popest/data/data-sets.html},
  urldate = {2026-10-12},
  note = {Accessed via Invokely, https://invokely.ai/rankings/population-18-64/illinois-counties?period=2016. Publisher attribution: U.S. Census Bureau. Population Estimates Program, county population by age and sex: residents aged 18 to 64 as a percentage of the total on 1 July, 2010 to 2019 from the 2010 to 2020 intercensal file and 2020 onwards from the latest vintage; states and the nation summed from counties. https://www.census.gov/programs-surveys/popest/data/data-sets.html. Retrieved 2026-10-12.},
}
RIS
TY  - DATA
AU  - U.S. Census Bureau
TI  - Population Estimates Program, county population by age and sex: residents aged 18 to 64 as a percentage of the total on 1 July, 2010 to 2019 from the 2010 to 2020 intercensal file and 2020 onwards from the latest vintage; states and the nation summed from counties: Counties in Illinois by population aged 18 to 64, 2016
PY  - 2026
DA  - 2026/06/25
PB  - U.S. Census Bureau
DB  - Invokely
UR  - https://www.census.gov/programs-surveys/popest/data/data-sets.html
L2  - https://invokely.ai/rankings/population-18-64/illinois-counties?period=2016
Y2  - 2026/10/12
N1  - Accessed via Invokely, https://invokely.ai/rankings/population-18-64/illinois-counties?period=2016.
N1  - Publisher attribution: U.S. Census Bureau. Population Estimates Program, county population by age and sex: residents aged 18 to 64 as a percentage of the total on 1 July, 2010 to 2019 from the 2010 to 2020 intercensal file and 2020 onwards from the latest vintage; states and the nation summed from counties. https://www.census.gov/programs-surveys/popest/data/data-sets.html. Retrieved 2026-10-12.
ER  -
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Questions

Which county has the highest population aged 18 to 64?

Brown County, with 69.2% in 2016, according to the U.S. Census Bureau.

Which county has the lowest population aged 18 to 64?

Jo Daviess County, with 54.8% in 2016.

Where does this ranking come from?

Every value comes from one source and one period, so the places are comparable: U.S. Census Bureau, Population Estimates Program, county population by age and sex: residents aged 18 to 64 as a percentage of the total on 1 July, 2010 to 2019 from the 2010 to 2020 intercensal file and 2020 onwards from the latest vintage; states and the nation summed from counties. Retrieved 2026-10-12.

Population aged 18 to 64: other rankings

Counties in Illinois: more rankings