White to Non-White Racial Dissimilarity (5-year estimate) Index for Custer County, MT was 25.25% in January of 2022, according to the United States Federal Reserve. Historically, White to Non-White Racial Dissimilarity (5-year estimate) Index for Custer County, MT reached a record high of 35.84 in January of 2009 and a record low of 11.07 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 Custer County, MT - last updated from the United States Federal Reserve on May of 2024.