Much is said about the ethnic patchwork of the United States, but this map highlights another kind of diversity: age. FRED’s county-level data on the age distribution of the U.S. population show large variations across the country and also within states. The spread of the range is also surprising. The youngest median age, 21.4 years, is in Lexington City County, Virginia—a small county that hosts two universities. The oldest median age, 65.3 years, is in Sumter County, Florida, where over half the residents live in a giant retirement community. Florida is expected to have a high median age, but other states also have counties with high median ages, including the admittedly small counties of Mineral, Colorado (60.9 years); Highland, Virginia (59.0 years); and Hooker, Nebraska (57.9 years).

How this map was created: The original post referenced an interactive map from our now discontinued GeoFRED site. The revised post provides a replacement map from FRED’s new mapping tool. To create FRED maps, go to the data series page in question and look for the green “VIEW MAP” button at the top right of the graph. See this post for instructions to edit a FRED map. Only series with a green map button can be mapped.
Suggested by Christian Zimmermann.