Income Inequality in McCook County, SD was 8.92585 Ratio in January of 2022, according to the United States Federal Reserve. Historically, Income Inequality in McCook County, SD reached a record high of 13.63315 in January of 2010 and a record low of 8.14785 in January of 2021. Trading Economics provides the current actual value, an historical data chart and related indicators for Income Inequality in McCook County, SD - last updated from the United States Federal Reserve on May of 2024.