Decatur County's 2026 population is estimated at 7,406, reflecting a -1.66% growth rate over the past year (World Population Review estimate based on U.S. Census Bureau data). Decatur County is the 87th largest county in Iowa. The 2010 population was 8,419 and has grown -12.03% since 2010.
Data after 2023 is projected based on recent change
Overall: 36.1 years
Female: 38.6 years
Male: 34.1 years
There are 6,038 adults, (1,639 of whom are seniors) in Decatur County.
Female: 3,909 (50.4%)
Male: 3,850 (49.6%)
The racial composition of Decatur County includes 91.78% White, and smaller percentages for other race, Black or African American, Asian, Native American, Native Hawaiian or Pacific Islander and multiracial populations.
| Race | Population ↓ | Percentage (of total) |
|---|---|---|
| White | 7,121 | 91.78% |
| Two or more races | 356 | 4.59% |
| Other race | 107 | 1.38% |
| Black or African American | 102 | 1.31% |
| Asian | 56 | 0.72% |
| Native American | 16 | 0.21% |
| Native Hawaiian or Pacific Islander | 1 | 0.01% |
Decatur County 's average per capita income is $41,572. Household income levels show a median of $59,044. The poverty rate stands at 14.56%.
| Name | Median ↓ | Mean |
|---|---|---|
| Married Families | $83,419 | - |
| Families | $75,313 | $92,355 |
| Households | $59,044 | $74,390 |
| Non Families | $36,786 | $44,710 |
Average Income
Median Household Income
Poverty Rate
