Resident Population in Lake County, SD was 11.03100 Thous. of Persons in January of 2023, according to the United States Federal Reserve. Historically, Resident Population in Lake County, SD reached a record high of 13.04500 in January of 2018 and a record low of 10.42500 in January of 1987. Trading Economics provides the current actual value, an historical data chart and related indicators for Resident Population in Lake County, SD - last updated from the United States Federal Reserve on May of 2024.