Resident Population in Miami County, KS was 35.73700 Thous. of Persons in January of 2024, according to the United States Federal Reserve. Historically, Resident Population in Miami County, KS reached a record high of 35.73700 in January of 2024 and a record low of 19.25400 in January of 1970. Trading Economics provides the current actual value, an historical data chart and related indicators for Resident Population in Miami County, KS - last updated from the United States Federal Reserve on April of 2026.