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Collection 5 Resources

Cook County, IL Population by Age

The median age in Cook County, IL is 37.3, as per 2021 ACS 5-Year Estimates. Of the total population, 18.15% were under the age of 15, 20.52% aged 15 to 29, 46.63% aged 30 to 64, 12.80% aged 65 to 84, and 1.90% were 85 years of age and older.
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By Neilsberg Research
Updated Sep 17, 2023

Cook County, IL population age distribution

A complete breakdown of Cook County's age demographics from 0 to 85 years, distributed across 18 age groups is listed in the table below.

Age Group Population % of Total Population
Under 5 years 312,408 5.93%
5 to 9 years 310,111 5.89%
10 to 14 years 333,249 6.33%
15 to 19 years 320,867 6.09%
20 to 24 years 332,370 6.31%
25 to 29 years 427,074 8.11%
30 to 34 years 417,287 7.93%
35 to 39 years 380,945 7.23%
40 to 44 years 343,237 6.52%
45 to 49 years 332,604 6.32%
50 to 54 years 328,397 6.24%
55 to 59 years 334,905 6.36%
60 to 64 years 317,665 6.03%
65 to 69 years 256,708 4.88%
70 to 74 years 198,839 3.78%
75 to 79 years 129,491 2.46%
80 to 84 years 89,004 1.69%
85 years and over 100,237 1.9%
Exploring Cook County's Diversity? Request Customized Data Now!

TABLE OF CONTENTS

Cook County, IL population by age group

Key stats
1,609,005
Population under 25 years
1,568,543
Population aged 25-44
1,313,571
Population aged 45-64
774,279
Population aged 65+

Sources: U.S. Census Bureau, American Community Survey (ACS) 2021

The graph shows Cook County's population by age group, with age group on x-axis and the respective age group's percent of the total population on y-axis
Cook County, IL population by age group. The largest age group was 25-29 years with a poulation of 427,074 (8.11% of the total population). Source: U.S. Census Bureau American Community Survey (ACS) 2017-2021 5-Year Estimates.

The largest age group in Cook County, IL was for the group of age 25-29 years with a population of 427,074 (8.11%), according to the 2021 American Community Survey.

At the same time, the smallest age group in Cook County, IL was the 80-84 years with a population of 89,004 (1.69%).

Cook County, IL population by age cohort

To better understand the age distribution of Cook County, IL's population, we divided it into the following 3 cohorts:

  • Children : Under the age of 18 years
  • Adults (working population): Between the age of 18 and 64 years
  • Seniors: 65 years and above
The pie chart shows Cook County's population divided into segments, with each segment representing an age cohort. The area of each segment is in the same proportion of a circle as the population of the cohort is of the total population.
Cook County, IL population by age cohorts (Children: Under 18 years; Working population: 18-64 years; Senior population: 65 years or more). The largest age group was 18 - 64 years with a poulation of 3,339,472 (63.42% of the total population). Source: U.S. Census Bureau American Community Survey (ACS) 2017-2021 5-Year Estimates.

Here's the population for each of the three cohorts.

Age Group Population % of Total Population
Under 18 years 1,151,647 21.87%
18 to 64 years 3,339,472 63.42%
85 years and over 774,279 14.71%
Exploring Cook County's Diversity? Request Customized Data Now!

Key stats for each age cohort as per our analysis of U.S. Census Bureau American Community Survey:

  • Cook County's population under 18 was 21.87%, compared to the 22.51% nationwide.
  • Cook County's working population (between 18 and 64) was 63.42%, compared to 61.45% nationwide.
  • Cook County's elderly or the senior population (over 65 age) was 14.71% as compared to 16.04% nationwide.

Cook County, IL population pyramid

Population pyramid for Cook County, IL is charted below using the estimates from U.S. Census Bureau's American Community Survey 5-Year estimates. A wide base suggests population increase, narrow base indicates declining birth rates.

Key stats from our analysis of the Cook County's population pyramid:

  • Youth dependency ratio, which is the number of children aged 0-14 per 100 persons aged 15-64, for Cook County, IL, is 27.0.
  • Old-age dependency ratio, which is the number of persons aged 65 or over per 100 persons aged 15-64, for Cook County, IL, is 21.9.
  • Total dependency ratio for Cook County, IL is 48.9.
  • Potential support ratio, which is the number of youth (working age population) per elderly, for Cook County, IL is 4.6.
The graph shows Cook County's population across different age group and gender, with population on x-axis and population y-axis. The male population is plotted on the left in blue color whereas the female population is plotted on the right in pink color.
Cook County, IL population pyramid i.e. Cook County population distrubution across age and gender. Source: U.S. Census Bureau American Community Survey (ACS) 2017-2021 5-Year Estimates.

Here's the Cook County, IL's male and female population across different age groups:

Age Group Population(Male) Population(Female) Total Population
Under 5 years 159,574 152,834 312,408
5 to 9 years 157,492 152,619 310,111
10 to 14 years 170,388 162,861 333,249
15 to 19 years 162,099 158,768 320,867
20 to 24 years 164,031 168,339 332,370
25 to 29 years 211,273 215,801 427,074
30 to 34 years 209,145 208,142 417,287
35 to 39 years 190,604 190,341 380,945
40 to 44 years 171,443 171,794 343,237
45 to 49 years 164,680 167,924 332,604
50 to 54 years 162,770 165,627 328,397
55 to 59 years 164,869 170,036 334,905
60 to 64 years 150,368 167,297 317,665
65 to 69 years 117,994 138,714 256,708
70 to 74 years 90,177 108,662 198,839
75 to 79 years 54,808 74,683 129,491
80 to 84 years 35,895 53,109 89,004
85 years and over 32,868 67,369 100,237
Exploring Cook County's Diversity? Request Customized Data Now!

Things to know

What is the population of Cook County, IL under 18?

Cook County's population under the age of 18 is 1,151,647, as per the latest U.S. Census Bureau's American Community Survey estimates. This population is 21.87% of the total resident population of Cook County, IL.

What is the aging population in Cook County, IL?

Cook County's population aged 65 years and above was 774,279. As per the U.S. Census Bureau's American Community Survey, this population is 14.71% of the entire population.

References

Datasets

Explore datasets by year of publication.
2023
Cook County, IL Age Group Population Dataset: A complete breakdown of Cook County age demographics from 0 to 85 years, distributed across 18 age groups
Last updated September 16, 2023
ACS
Free
Neilsberg
CSV, JSON
2017-2021
CC BY 4.0
About this dataset

Context

The dataset tabulates the Cook County population distribution across 18 age groups. It lists the population in each age group along with the percentage population relative of the total population for Cook County. The dataset can be utilized to understand the population distribution of Cook County by age. For example, using this dataset, we can identify the largest age group in Cook County.

Key observations

The largest age group in Cook County, IL was for the group of age 25-29 years with a population of 427,074 (8.11%), according to the 2021 American Community Survey. At the same time, the smallest age group in Cook County, IL was the 80-84 years with a population of 89,004 (1.69%). Source: U.S. Census Bureau American Community Survey (ACS) 2017-2021 5-Year Estimates.

Cook County population by age group

Content

When available, the data consists of estimates from the U.S. Census Bureau American Community Survey (ACS) 2017-2021 5-Year Estimates.

Age groups:

  • Under 5 years
  • 5 to 9 years
  • 10 to 14 years
  • 15 to 19 years
  • 20 to 24 years
  • 25 to 29 years
  • 30 to 34 years
  • 35 to 39 years
  • 40 to 44 years
  • 45 to 49 years
  • 50 to 54 years
  • 55 to 59 years
  • 60 to 64 years
  • 65 to 69 years
  • 70 to 74 years
  • 75 to 79 years
  • 80 to 84 years
  • 85 years and over

Variables / Data Columns

  • Age Group: This column displays the age group in consideration
  • Population: The population for the specific age group in the Cook County is shown in this column.
  • % of Total Population: This column displays the population of each age group as a proportion of Cook County total population. Please note that the sum of all percentages may not equal one due to rounding of values.

Good to know

Margin of Error

Data in the dataset are based on the estimates and are subject to sampling variability and thus a margin of error. Neilsberg Research recommends using caution when presening these estimates in your research.

Custom data

If you do need custom data for any of your research project, report or presentation, you can contact our research staff at research@neilsberg.com for a feasibility of a custom tabulation on a fee-for-service basis.

Inspiration

Neilsberg Research Team curates, analyze and publishes demographics and economic data from a variety of public and proprietary sources, each of which often includes multiple surveys and programs. The large majority of Neilsberg Research aggregated datasets and insights is made available for free download at https://www.neilsberg.com/research/.

Recommended for further research

This dataset is a part of the main dataset for Cook County Population by Age. You can refer the same here

Cook County, IL Age Cohorts Dataset: Children, Working Adults, and Seniors in Cook County - Population and Percentage Analysis
Last updated September 16, 2023
ACS
Free
Neilsberg
CSV, JSON
2017-2021
CC BY 4.0
About this dataset

Context

The dataset tabulates the Cook County population by age cohorts (Children: Under 18 years; Working population: 18-64 years; Senior population: 65 years or more). It lists the population in each age cohort group along with its percentage relative to the total population of Cook County. The dataset can be utilized to understand the population distribution across children, working population and senior population for dependency ratio, housing requirements, ageing, migration patterns etc.

Key observations

The largest age group was $b3_v1 with a poulation of $b3_v2 ($b3_v3 of the total population). Source: U.S. Census Bureau American Community Survey (ACS) 2017-2021 5-Year Estimates.

Cook County population by age cohort

Content

When available, the data consists of estimates from the U.S. Census Bureau American Community Survey (ACS) 2017-2021 5-Year Estimates.

Age cohorts:

  • Under 18 years
  • 18 to 64 years
  • 65 years and over

Variables / Data Columns

  • Age Group: This column displays the age cohort for the Cook County population analysis. Total expected values are 3 groups ( Children, Working Population and Senior Population).
  • Population: The population for the age cohort in Cook County is shown in the following column.
  • Percent of Total Population: The population as a percent of total population of the Cook County is shown in the following column.

Good to know

Margin of Error

Data in the dataset are based on the estimates and are subject to sampling variability and thus a margin of error. Neilsberg Research recommends using caution when presening these estimates in your research.

Custom data

If you do need custom data for any of your research project, report or presentation, you can contact our research staff at research@neilsberg.com for a feasibility of a custom tabulation on a fee-for-service basis.

Inspiration

Neilsberg Research Team curates, analyze and publishes demographics and economic data from a variety of public and proprietary sources, each of which often includes multiple surveys and programs. The large majority of Neilsberg Research aggregated datasets and insights is made available for free download at https://www.neilsberg.com/research/.

Recommended for further research

This dataset is a part of the main dataset for Cook County Population by Age. You can refer the same here

Cook County, IL Population Pyramid Dataset: Age Groups, Male and Female Population, and Total Population for Demographics Analysis
Last updated September 16, 2023
ACS
Free
Neilsberg
CSV, JSON
2017-2021
CC BY 4.0
About this dataset

Context

The dataset tabulates the data for the Cook County, IL population pyramid, which represents the Cook County population distribution across age and gender, using estimates from the U.S. Census Bureau American Community Survey 5-Year estimates. It lists the male and female population for each age group, along with the total population for those age groups. Higher numbers at the bottom of the table suggest population growth, whereas higher numbers at the top indicate declining birth rates. Furthermore, the dataset can be utilized to understand the youth dependency ratio, old-age dependency ratio, total dependency ratio, and potential support ratio.

Key observations

  • Youth dependency ratio, which is the number of children aged 0-14 per 100 persons aged 15-64, for Cook County, IL, is 27.0.
  • Old-age dependency ratio, which is the number of persons aged 65 or over per 100 persons aged 15-64, for Cook County, IL, is 21.9.
  • Total dependency ratio for Cook County, IL is 48.9.
  • Potential support ratio, which is the number of youth (working age population) per elderly, for Cook County, IL is 4.6.

Cook County population pyramid

Content

When available, the data consists of estimates from the U.S. Census Bureau American Community Survey (ACS) 2017-2021 5-Year Estimates.

Age groups:

  • Under 5 years
  • 5 to 9 years
  • 10 to 14 years
  • 15 to 19 years
  • 20 to 24 years
  • 25 to 29 years
  • 30 to 34 years
  • 35 to 39 years
  • 40 to 44 years
  • 45 to 49 years
  • 50 to 54 years
  • 55 to 59 years
  • 60 to 64 years
  • 65 to 69 years
  • 70 to 74 years
  • 75 to 79 years
  • 80 to 84 years
  • 85 years and over

Variables / Data Columns

  • Age Group: This column displays the age group for the Cook County population analysis. Total expected values are 18 and are define above in the age groups section.
  • Population (Male): The male population in the Cook County for the selected age group is shown in the following column.
  • Population (Female): The female population in the Cook County for the selected age group is shown in the following column.
  • Total Population: The total population of the Cook County for the selected age group is shown in the following column.

Good to know

Margin of Error

Data in the dataset are based on the estimates and are subject to sampling variability and thus a margin of error. Neilsberg Research recommends using caution when presening these estimates in your research.

Custom data

If you do need custom data for any of your research project, report or presentation, you can contact our research staff at research@neilsberg.com for a feasibility of a custom tabulation on a fee-for-service basis.

Inspiration

Neilsberg Research Team curates, analyze and publishes demographics and economic data from a variety of public and proprietary sources, each of which often includes multiple surveys and programs. The large majority of Neilsberg Research aggregated datasets and insights is made available for free download at https://www.neilsberg.com/research/.

Recommended for further research

This dataset is a part of the main dataset for Cook County Population by Age. You can refer the same here

If you're looking for datasets from another year, please feel free to contact us at research@neilsberg.com and we'll be happy to assist you further.

Explore related topics

Cook County, IL Demographics Cook County, IL Population

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Neilsberg Research
Neilsberg Research team are data scientists with expertise in processing, analysis and visualization of big data helping small businesses make right decisions.
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Collection 5 Resources