Resident Population in Grant County, WI was 51.40900 Thous. of Persons in January of 2023, according to the United States Federal Reserve. Historically, Resident Population in Grant County, WI reached a record high of 52.10900 in January of 1981 and a record low of 48.39800 in January of 1970. Trading Economics provides the current actual value, an historical data chart and related indicators for Resident Population in Grant County, WI - last updated from the United States Federal Reserve on May of 2024.