Resident Population in Cass County, IA was 13.13000 Thous. of Persons in January of 2023, according to the United States Federal Reserve. Historically, Resident Population in Cass County, IA reached a record high of 17.20000 in January of 1971 and a record low of 12.82200 in January of 2019. Trading Economics provides the current actual value, an historical data chart and related indicators for Resident Population in Cass County, IA - last updated from the United States Federal Reserve on May of 2024.