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

Counties in Iowa by population aged 18 to 64

Story County had the highest population aged 18 to 64 of 99 counties in 2014, at 72.1%. Ringgold County had the lowest, at 51.8%. The median was 57.4% and the figure for Iowa was 60.6%. Source: the U.S. Census Bureau.

Highest72.1Story County
Lowest51.8Ringgold County
Median57.499 counties
Iowa60.6History

Top 40 counties, 2014

Story County: 72.1 %Story County72.1Johnson County: 69.5 %Johnson County69.5Black Hawk County: 63.5 %Black Hawk County63.5Jefferson County: 63.4 %Jefferson County63.4Polk County: 62.8 %Polk County62.8Winneshiek County: 62.7 %Winneshiek County62.7Linn County: 61.6 %Linn County61.6Scott County: 61.4 %Scott County61.4Webster County: 61.1 %Webster County61.1Poweshiek County: 60.7 %Poweshiek County60.7Pottawattamie County: 60.7 %Pottawattamie County60.7Dubuque County: 60.6 %Dubuque County60.6Wapello County: 60.1 %Wapello County60.1Dallas County: 60 %Dallas County60Woodbury County: 60 %Woodbury County60Buena Vista County: 60 %Buena Vista County60Henry County: 59.9 %Henry County59.9Jones County: 59.9 %Jones County59.9Cerro Gordo County: 59.7 %Cerro Gordo County59.7Louisa County: 59.6 %Louisa County59.6Decatur County: 59.6 %Decatur County59.6Muscatine County: 59.5 %Muscatine County59.5Mills County: 59.5 %Mills County59.5Warren County: 59.5 %Warren County59.5Benton County: 59.3 %Benton County59.3Jasper County: 59.3 %Jasper County59.3Boone County: 59.2 %Boone County59.2Lee County: 59.2 %Lee County59.2Bremer County: 59.1 %Bremer County59.1Marion County: 59 %Marion County59Mahaska County: 59 %Mahaska County59Clinton County: 58.9 %Clinton County58.9Iowa County: 58.7 %Iowa County58.7Winnebago County: 58.7 %Winnebago County58.7Cedar County: 58.6 %Cedar County58.6Sioux County: 58.3 %Sioux County58.3Fayette County: 58.3 %Fayette County58.3Des Moines County: 58.2 %Des Moines County58.2Page County: 58.2 %Page County58.2Union County: 58.1 %Union County58.1
%. Source: Invokely calculation with data from U.S. Census Bureau. Retrieved 2026-10-12.

Full ranking

RankCounties2014 (%)Change on 2013
1Story County72.10 pts
2Johnson County69.5-0.5 pts
3Black Hawk County63.5-0.3 pts
4Jefferson County63.4-1.1 pts
5Polk County62.8-0.2 pts
6Winneshiek County62.7-0.3 pts
7Linn County61.6-0.3 pts
8Scott County61.4-0.4 pts
9Webster County61.1-0.1 pts
10Poweshiek County60.7+0.3 pts
11Pottawattamie County60.7-0.3 pts
12Dubuque County60.6-0.3 pts
13Wapello County60.1-0 pts
14Dallas County60-0.3 pts
15Woodbury County60-0.2 pts
16Buena Vista County60-0.1 pts
17Henry County59.9-0.4 pts
18Jones County59.9-0.1 pts
19Cerro Gordo County59.7-0.2 pts
20Louisa County59.60 pts
21Decatur County59.6-0.9 pts
22Muscatine County59.5-0.2 pts
23Mills County59.5-0.5 pts
24Warren County59.5-0.3 pts
25Benton County59.3-0.1 pts
26Jasper County59.3-0.5 pts
27Boone County59.2-0.2 pts
28Lee County59.2-0.6 pts
29Bremer County59.1-0.6 pts
30Marion County59-0.1 pts
31Mahaska County59-0.1 pts
32Clinton County58.9-0.2 pts
33Iowa County58.7-0 pts
34Winnebago County58.7-0.5 pts
35Cedar County58.6-0.3 pts
36Sioux County58.3-0.3 pts
37Fayette County58.3-0.1 pts
38Des Moines County58.2-0.4 pts
39Page County58.2-0.1 pts
40Union County58.1+0.4 pts
41Delaware County58.1-0.4 pts
42Jackson County58.1-0.1 pts
43Harrison County58.1-0.4 pts
44Worth County58-0.5 pts
45Emmet County57.9-0.8 pts
46Clarke County57.9-0.2 pts
47Clay County57.5-0.5 pts
48Marshall County57.5-0.4 pts
49Hamilton County57.40 pts
50Calhoun County57.4+0.2 pts
51Plymouth County57.2-0.2 pts
52Osceola County57-0.2 pts
53Franklin County57-0.3 pts
54Madison County56.9-0.5 pts
55Carroll County56.9-0.2 pts
56Tama County56.9+0.1 pts
57Dickinson County56.8-0.5 pts
58Chickasaw County56.8-0.6 pts
59Humboldt County56.8+0.4 pts
60Clayton County56.7-0.7 pts
61Crawford County56.7-0.1 pts
62Buchanan County56.7-0.5 pts
63Allamakee County56.7-0.3 pts
64Cherokee County56.7-0.5 pts
65Hancock County56.6-0.2 pts
66Monroe County56.6-0.3 pts
67Washington County56.6-0.4 pts
68Montgomery County56.50 pts
69Hardin County56.4+0.1 pts
70Appanoose County56.3-0.6 pts
71Keokuk County56.2-0.6 pts
72Palo Alto County56.2-0.5 pts
73Floyd County56.2-0.4 pts
74Fremont County56.1-1.1 pts
75Grundy County56.1-0.5 pts
76Cass County56.1+0.1 pts
77Kossuth County560 pts
78Adair County56-0.7 pts
79Van Buren County55.9-0.3 pts
80Wright County55.80 pts
81Lucas County55.8-0.2 pts
82Adams County55.7-1.5 pts
83O'Brien County55.6-0.5 pts
84Sac County55.5+0.2 pts
85Greene County55.5-0.2 pts
86Guthrie County55.5-0.8 pts
87Audubon County55.5-0 pts
88Pocahontas County55.4-0.3 pts
89Taylor County55.4-0.4 pts
90Shelby County55.3-0.1 pts
91Howard County55.2-0 pts
92Butler County55.2-0.5 pts
93Ida County55.1-0.2 pts
94Lyon County54.7-0.5 pts
95Monona County54.4-0.2 pts
96Mitchell County53.90 pts
96Wayne County53.9-0.2 pts
98Davis County53.9+0.1 pts
99Ringgold County51.8+0.3 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 Iowa by population aged 18 to 64, 2014) [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 Iowa by population aged 18 to 64, 2014. 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/iowa-counties?period=2014. 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 Iowa by population aged 18 to 64, 2014. 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/iowa-counties?period=2014.

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 Iowa by population aged 18 to 64, 2014 [Dataset]. Available at: https://www.census.gov/programs-surveys/popest/data/data-sets.html, via Invokely: https://invokely.ai/rankings/population-18-64/iowa-counties?period=2014 (Accessed: 12 October 2026).

BibTeX
@misc{census_counties_in_iowa_by_2014,
  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 Iowa by population aged 18 to 64, 2014}},
  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/iowa-counties?period=2014. 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 Iowa by population aged 18 to 64, 2014
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/iowa-counties?period=2014
Y2  - 2026/10/12
N1  - Accessed via Invokely, https://invokely.ai/rankings/population-18-64/iowa-counties?period=2014.
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?

Story County, with 72.1% in 2014, according to the U.S. Census Bureau.

Which county has the lowest population aged 18 to 64?

Ringgold County, with 51.8% in 2014.

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 Iowa: more rankings