The median income of Fond du Lac County residents was an inflation-adjusted $30,188 per year. Fond du Lac County had 41,387 households in 2017, with a population of 102,082.
The county with the highest median resident income in the state was Waukesha County. Waukesha County's median income was $38,295 per year after adjusting for inflation – $8,107 more than Fond du Lac County. It had 156,996 households in 2017 and a population of 396,731.
Menominee County had the lowest annual resident income among counties in Wisconsin, with a median income of only $21,854 per year. That was $8,334 less than the median income in Fond du Lac County at the time. Menominee County had 1,354 households in 2017 and a population of 4,506.
The table below shows the state's counties ranked by median annual resident earnings in 2017.