White to Non-White Racial Dissimilarity (5-year estimate) Index for Madison County, IA was 24.14% in January of 2022, according to the United States Federal Reserve. Historically, White to Non-White Racial Dissimilarity (5-year estimate) Index for Madison County, IA reached a record high of 26.20 in January of 2010 and a record low of 16.98 in January of 2011. Trading Economics provides the current actual value, an historical data chart and related indicators for White to Non-White Racial Dissimilarity (5-year estimate) Index for Madison County, IA - last updated from the United States Federal Reserve on May of 2024.