Resident Population in Clay County, KY was 19.64800 Thous. of Persons in January of 2023, according to the United States Federal Reserve. Historically, Resident Population in Clay County, KY reached a record high of 24.52200 in January of 1999 and a record low of 18.48100 in January of 1970. Trading Economics provides the current actual value, an historical data chart and related indicators for Resident Population in Clay County, KY - last updated from the United States Federal Reserve on May of 2024.