The median income of Boone County residents was an inflation-adjusted $31,297 per year. Boone County had 10,998 households in 2017, with a population of 26,381.
The county with the highest median resident income in the state was Dallas County. Dallas County's median income was $42,700 per year after adjusting for inflation – $11,403 more than Boone County. It had 31,363 households in 2017 and a population of 80,864.
Decatur County had the lowest annual resident income among counties in Iowa, with a median income of only $19,872 per year. That was $11,425 less than the median income in Boone County at the time. Decatur County had 3,172 households in 2017 and a population of 8,105.
The table below shows the state's counties ranked by median annual resident earnings in 2017.