O Brien County, IA population age distributions
A complete breakdown of O Brien 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 | 932 | 6.61% |
| 5 to 9 years | 1,065 | 7.55% |
| 10 to 14 years | 912 | 6.47% |
| 15 to 19 years | 810 | 5.74% |
| 20 to 24 years | 736 | 5.22% |
| 25 to 29 years | 879 | 6.23% |
| 30 to 34 years | 811 | 5.75% |
| 35 to 39 years | 958 | 6.79% |
| 40 to 44 years | 804 | 5.7% |
| 45 to 49 years | 662 | 4.69% |
| 50 to 54 years | 751 | 5.33% |
| 55 to 59 years | 738 | 5.23% |
| 60 to 64 years | 1,072 | 7.6% |
| 65 to 69 years | 909 | 6.45% |
| 70 to 74 years | 660 | 4.68% |
| 75 to 79 years | 403 | 2.86% |
| 80 to 84 years | 358 | 2.54% |
| 85 years and over | 643 | 4.56% |
TABLE OF CONTENTS
O Brien County, IA population by age group
Sources: U.S. Census Bureau, American Community Survey (ACS) 2019-2023
FIGURE 1
O Brien County, IA population by age group.
The largest age group is 60 to 64 years with a population of 1,072 (7.60% of the total population).
The largest age group in O Brien County, IA was for the group of age 60 to 64 years with a population of 1,072 (7.60%), according to the 2019-2023 American Community Survey.
At the same time, the smallest age group in O Brien County, IA was the 80 to 84 years with a population of 358 (2.54%).
O Brien County, IA population by age cohort
To better understand the age distribution of O Brien County, IA'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
FIGURE 2
O Brien County, IA population by age cohort
The largest age group was 18 to 64 years with a population of 7,692 (54.54% of the total population).
Key stats for each age cohort as per our analysis of U.S. Census Bureau American Community Survey:
- O Brien County 's population under 18 was 24.38%, compared to the 22.16% nationwide.
- O Brien County's working population (between 18 and 64) was 54.54%, compared to 61% nationwide.
- O Brien County's elderly or the senior population (over 65 age) was 21.08% as compared to 16.84% nationwide.
O Brien County, IA population pyramid
Population pyramid for O Brien County, IA 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 O Brien County's population pyramid:
- Youth dependency ratio, which is the number of children aged 0-14 per 100 persons aged 15-64, for O Brien County, IA, is 35.4.
- Old-age dependency ratio, which is the number of persons aged 65 or over per 100 persons aged 15-64, for O Brien County, IA, is 36.2.
- Total dependency ratio for O Brien County, IA is 71.5.
- Potential support ratio, which is the number of youth (working age population) per elderly, for O Brien County, IA is 2.8.
FIGURE 3
O Brien County, IA population pyramid
O Brien County population distrubution across age and gender. A wide base suggests population increase, narrow base indicates declining birth rates.
O Brien County, IA population pyramid
Here's the O Brien County, IA's male and female population across different age groups .
| Age Group | Population(Male) | Population(Female) | Total Population |
|---|---|---|---|
| Under 5 years | 490 | 442 | 932 |
| 5 to 9 years | 559 | 506 | 1,065 |
| 10 to 14 years | 433 | 479 | 912 |
| 15 to 19 years | 418 | 392 | 810 |
| 20 to 24 years | 423 | 313 | 736 |
| 25 to 29 years | 440 | 439 | 879 |
| 30 to 34 years | 401 | 410 | 811 |
| 35 to 39 years | 500 | 458 | 958 |
| 40 to 44 years | 402 | 402 | 804 |
| 45 to 49 years | 327 | 335 | 662 |
| 50 to 54 years | 419 | 332 | 751 |
| 55 to 59 years | 404 | 334 | 738 |
| 60 to 64 years | 491 | 581 | 1,072 |
| 65 to 69 years | 517 | 392 | 909 |
| 70 to 74 years | 270 | 390 | 660 |
| 75 to 79 years | 209 | 194 | 403 |
| 80 to 84 years | 106 | 252 | 358 |
| 85 years and over | 226 | 417 | 643 |
Things to know
What is the population of O Brien County, IA under 18?
O Brien County's population under the age of 18 is 3,438, as per the latest U.S. Census Bureau's American Community Survey estimates. This population is 24.38% of the total resident population of O Brien County, IA.
What is the aging population in O Brien County, IA?
O Brien County's population aged 65 years and above was 2,973. As per the U.S. Census Bureau's American Community Survey, this population is 21.08% of the entire population.
References
- U.S. Census Bureau American Community Survey (ACS) 2019-2023 5-Year Estimates