Resident Population in Fayette County, IA was 19.21000 Thous. of Persons in January of 2023, according to the United States Federal Reserve. Historically, Resident Population in Fayette County, IA reached a record high of 27.10000 in January of 1972 and a record low of 19.21000 in January of 2023. Trading Economics provides the current actual value, an historical data chart and related indicators for Resident Population in Fayette County, IA - last updated from the United States Federal Reserve on May of 2024.