Rock Island County, Illinois Age & Gender Distribution (2024)
Population distribution by age and gender for Rock Island County, Illinois
Rock Island County, Illinois Age & Gender Statistics (2024)
Total Population
142,757
Median Age
40.3
Male Median
39.0
Female Median
41.3
Rock Island County, Illinois Population Growth
Rock Island County, Illinois Demographic Trend
Since 2010, the population of has changed by -3.2%%.
-3.2%% Growth
Rock Island County, Illinois Age & Gender Pyramid
Figure 2: Population distribution by age and gender for 2024.
Rock Island County, Illinois Historical Population Data
| Year | Median Age | Population |
|---|---|---|
| 2024 | 40.3 | 142,757 |
| 2023 | 40.3 | 142,995 |
| 2022 | 40.2 | 143,819 |
| 2021 | 40.1 | 144,694 |
| 2020 | 40.1 | 142,801 |
| 2019 | 40.1 | 143,873 |
| 2018 | 40.1 | 145,275 |
| 2017 | 40.0 | 146,205 |
| 2016 | 40.1 | 146,536 |
| 2015 | 40.0 | 147,161 |
| 2014 | 40.1 | 146,964 |
| 2013 | 40.0 | 147,477 |
| 2012 | 40.1 | 147,504 |
| 2011 | 39.8 | 147,625 |
| 2010 | 39.7 | 147,524 |
Rock Island County, Illinois Age Group Breakdown (2024)
| Age Cohort | Percentage |
|---|---|
| Under 5 | 5.8% |
| 5–17 | 16.7% |
| 18–24 | 8.9% |
| 25–34 | 12.0% |
| 35–54 | 23.6% |
| 55–64 | 12.6% |
| 65+ | 20.4% |
Dependency Ratios for Rock Island County, Illinois
- Total Dependency Ratio:
- 74.9
- Youth Dependency:
- 39.3
- Old-Age Dependency:
- 35.6
The dependency ratio measures dependents (ages 0-17 and 65+) per 100 working-age individuals (ages 18-64).
Age & Gender FAQs for Rock Island County, Illinois
The median age in Rock Island County, Illinois is 40.3 years.
According to latest Census data, the total population of Rock Island County, Illinois is 142,757.
In Rock Island County, Illinois, seniors (ages 65+) make up 20.4% of the population, while children under 18 represent 16.7%.
Based on historical data since 2010, the population in Rock Island County, Illinois has remained stable.