White to Non-White Racial Dissimilarity (5-year estimate) Index for McCurtain County, OK was 27.67% in January of 2022, according to the United States Federal Reserve. Historically, White to Non-White Racial Dissimilarity (5-year estimate) Index for McCurtain County, OK reached a record high of 43.30 in January of 2010 and a record low of 27.02 in January of 2020. 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 McCurtain County, OK - last updated from the United States Federal Reserve on May of 2024.