White to Non-White Racial Dissimilarity (5-year estimate) Index for Johnson County, IL was 61.43% in January of 2022, according to the United States Federal Reserve. Historically, White to Non-White Racial Dissimilarity (5-year estimate) Index for Johnson County, IL reached a record high of 86.80 in January of 2019 and a record low of 51.23 in January of 2014. 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 Johnson County, IL - last updated from the United States Federal Reserve on May of 2024.