(CNSNews.com) - When measured by median age, Sumter County, Fla., had the oldest population of any county in the country in 2016, according to data published by the U.S. Census Bureau. Lexington City, Va., had the youngest.
In Sumter County, the median age was 67.1. In Lexington City, the median age was 22.7. (Independent cities in Virginia are treated as counties by the Census Bureau.)
Michigan had more counties (4) than Florida (3) that ranked among the nation’s 20 most elderly counties. These included Alcona County, which ranked No. 5 with a median age of 58.1; Otonagon County, which tied for No. 6 with a median age of 58.0; Keweenaw County, which tied for No. 13 with a median age of 56.7; and Montmorency County, which tied for No. 20 with a median age of 55.9.
Texas, New Mexico and Virginia also had three counties each in the Top 20 for oldest population.
Sumter County—with the nation’s oldest population—is in central Florida, bordering on neither the Gulf Coast nor the Atlantic.
It had a population of 123,996 in 2016, according to the Census Bureau. Of that population, 56.3 percent were 65 years old or older and only 7.1 percent was 18 or younger.
In the 2016 presidential election, it went for Republican candidate Donald Trump over Democratic candidate Hillary Clinton by 68.27 percent to 29.31 percent.
Sumter is dramatically different from the county with the second oldest population in the nation--Karawao County, Hawaii, which had only 88 residents in 2016, according to the Census Bureau.
Karawao County, which is on the island of Molokai, was originally set up to serve as a quarantined area for people suffering from Hansen’s disease (leprosy). It is administered by the Hawaii Department of Public Health and does not have a county government. Much of it is now a National Historical Park.
“This place was chosen to isolate people with, what was at that time, an incurable illness,” says a “brief history” of the area published by the National Park Service. “The peninsula was remote and fairly inaccessible.”
“After World War II, dramatic changes in both the treatment of Hansen's disease and in social attitudes towards patients occurred with the discovery of sulfone drugs,” says the NPS history. “Essentially a cure for the disease, the drugs were introduced into Hawaii in 1946.”
“With the new drug therapies, Hansen's disease patients were no longer contagious,” says the history. “There was no further need for isolation. In 1969 the century-old laws of forced quarantine were abolished. Former patients living in Kalaupapa today have chosen to remain here, most for the rest of their lives.”
Saint Damien de Veuster served as a missionary here from 1873 to 1889, before he himself died of leprosy.
Lexington City, Va., the nation’s youngest county by median age (22.7), had a population of only 7,045 in 2016. Despite its very young median age, 43.8 percent of the population in Lexington has a bachelor’s degree or higher. It is the home of Washington and Lee University.
Madison County, Idaho, the nation’s second youngest county (23.2), had a population of 29,048, with 27.3 percent of that population being 18 or younger. It is the home to Brigham Young University-Idaho.