Counties in Colorado by population aged 18 to 64
Crowley County had the highest population aged 18 to 64 of 64 counties in 2015, at 75%. Hinsdale County had the lowest, at 51.5%. The median was 61.2% and the figure for Colorado was 63.8%. Source: the U.S. Census Bureau.
Top 40 counties, 2015
Full ranking
| Rank | Counties | 2015 (%) | Change on 2014 |
|---|---|---|---|
| 1 | Crowley County | 75 | +0.9 pts |
| 2 | Summit County | 72.8 | -0.1 pts |
| 3 | Gunnison County | 69.9 | -0.2 pts |
| 4 | San Miguel County | 69.6 | -0.6 pts |
| 5 | Bent County | 68.5 | +0.2 pts |
| 6 | Denver County | 68.4 | +0.2 pts |
| 7 | Pitkin County | 68 | -0.2 pts |
| 8 | Eagle County | 68 | -0.3 pts |
| 9 | Gilpin County | 67.9 | -0.7 pts |
| 10 | Routt County | 67.6 | -0.6 pts |
| 11 | Boulder County | 67.2 | -0.2 pts |
| 12 | Lake County | 66.9 | +0.5 pts |
| 13 | Grand County | 66.9 | -0.3 pts |
| 14 | Clear Creek County | 65.9 | -0.9 pts |
| 15 | Park County | 65.6 | -1.3 pts |
| 16 | La Plata County | 65.4 | -0.6 pts |
| 17 | Larimer County | 65.1 | -0.3 pts |
| 18 | Logan County | 64.7 | -0.3 pts |
| 19 | Jefferson County | 64 | -0.2 pts |
| 20 | Broomfield County | 63.4 | +0.2 pts |
| 21 | Arapahoe County | 63.4 | -0.2 pts |
| 22 | El Paso County | 63.3 | -0.1 pts |
| 23 | Lincoln County | 63.1 | +0.4 pts |
| 24 | Garfield County | 63.1 | -0.2 pts |
| 25 | Elbert County | 63 | -0.6 pts |
| 26 | San Juan County | 62.9 | -2.1 pts |
| 27 | Fremont County | 62.8 | -0.3 pts |
| 28 | Adams County | 62.7 | -0 pts |
| 29 | Teller County | 62.1 | -0.7 pts |
| 30 | Alamosa County | 61.8 | -0.7 pts |
| 31 | Weld County | 61.6 | -0.1 pts |
| 32 | Kit Carson County | 61.2 | +0.4 pts |
| 33 | Douglas County | 61.2 | -0.2 pts |
| 34 | Moffat County | 60.8 | -0.4 pts |
| 35 | Rio Blanco County | 60.7 | -0.1 pts |
| 36 | Chaffee County | 60.5 | -0.3 pts |
| 37 | Mesa County | 60.3 | -0.3 pts |
| 38 | Jackson County | 60.1 | -0.7 pts |
| 39 | Pueblo County | 59.3 | -0.3 pts |
| 40 | Ouray County | 59.1 | -0.4 pts |
| 41 | Dolores County | 58.9 | -0 pts |
| 42 | Las Animas County | 58.8 | -0.6 pts |
| 43 | Prowers County | 57.9 | -0.1 pts |
| 44 | Saguache County | 57.8 | -1.2 pts |
| 45 | Montezuma County | 57.8 | -0.6 pts |
| 46 | Morgan County | 57.6 | -0.2 pts |
| 47 | Washington County | 56.9 | -0.3 pts |
| 48 | Yuma County | 56.7 | 0 pts |
| 49 | Archuleta County | 56.7 | -1.5 pts |
| 50 | Rio Grande County | 56.6 | -0.5 pts |
| 51 | Otero County | 56.2 | -0.4 pts |
| 52 | Cheyenne County | 56.1 | -0.6 pts |
| 53 | Mineral County | 56 | -3.4 pts |
| 54 | Montrose County | 56 | -0.2 pts |
| 55 | Kiowa County | 55.5 | -0.8 pts |
| 56 | Phillips County | 55 | -0.5 pts |
| 57 | Delta County | 55 | -0.5 pts |
| 58 | Sedgwick County | 54.6 | -1 pts |
| 59 | Baca County | 54.3 | +0.1 pts |
| 60 | Costilla County | 54.1 | -1.5 pts |
| 61 | Conejos County | 53.7 | -0.6 pts |
| 62 | Custer County | 53.6 | -2.2 pts |
| 63 | Huerfano County | 53.5 | -1 pts |
| 64 | Hinsdale County | 51.5 | -3.4 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
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 Colorado by population aged 18 to 64, 2015) [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 Colorado by population aged 18 to 64, 2015. 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/colorado-counties?period=2015. 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 Colorado by population aged 18 to 64, 2015. 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/colorado-counties?period=2015.
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 Colorado by population aged 18 to 64, 2015 [Dataset]. Available at: https://www.census.gov/programs-surveys/popest/data/data-sets.html, via Invokely: https://invokely.ai/rankings/population-18-64/colorado-counties?period=2015 (Accessed: 12 October 2026).
BibTeX
@misc{census_counties_in_colorado_by_2015,
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 Colorado by population aged 18 to 64, 2015}},
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/colorado-counties?period=2015. 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 Colorado by population aged 18 to 64, 2015
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/colorado-counties?period=2015
Y2 - 2026/10/12
N1 - Accessed via Invokely, https://invokely.ai/rankings/population-18-64/colorado-counties?period=2015.
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 -
Use this data in your AI agent
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Rank Counties in Colorado by population aged 18 to 64 using official data, and cite the source.
rank_places {"indicator":"population_18_64_share","level":"province","within":"Colorado","limit":10}
GET https://invokely.ai/api/v1/rank?indicator=population_18_64_share&level=province&within=Colorado&limit=10Questions
Which county has the highest population aged 18 to 64?
Crowley County, with 75% in 2015, according to the U.S. Census Bureau.
Which county has the lowest population aged 18 to 64?
Hinsdale County, with 51.5% in 2015.
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.