Resident Population in Mercer County, ND was 8.34800 Thous. of Persons in January of 2024, according to the United States Federal Reserve. Historically, Resident Population in Mercer County, ND reached a record high of 12.29000 in January of 1984 and a record low of 6.17500 in January of 1970. Trading Economics provides the current actual value, an historical data chart and related indicators for Resident Population in Mercer County, ND - last updated from the United States Federal Reserve on April of 2026.