Resident Population in Niobrara County, WY was 2.35400 Thous. of Persons in January of 2023, according to the United States Federal Reserve. Historically, Resident Population in Niobrara County, WY reached a record high of 3.28800 in January of 1984 and a record low of 2.23300 in January of 2006. Trading Economics provides the current actual value, an historical data chart and related indicators for Resident Population in Niobrara County, WY - last updated from the United States Federal Reserve on May of 2024.