Shrinking, aging, withering away

We hear much about two enormous U.S. and global trends — urbanization and aging. In most countries, people are fleeing to the city, and the population on average is getting older.

Details: Here in Iowa, you can see this happening in real time: The state's 19 "micropolitans" — population centers outside the gravitational pull of any big city, which exercise their own pull on smaller communities in their own region — are shrinking and aging.

Why it matters: When you think of family farms and rural America — the bedrock of much of the country's traditions — those communities survive as a piece of the micropolitan orbit. The micropolitans "are the anchor socially, culturally, economically," says David Swenson, an economics professor at Iowa State.

• In recent decades, though, local jobs in manufacturing and businesses that grow up around them have been withering up, leading young Iowans to move to larger cities for work.

Two examples: As you see above, Cerro Gordo County's 65-and-over population surged to 20.6% in 2016 from 11.8% in 1970, according to data compiled by Swenson. In Dickenson County, one out of four people are 65 or older, compared with 14.2% in 1970.

• On average, senior Iowans are now 18.6% of the micropolitans, up from 11.6% in 1970.
• The state as a whole has aged, too — with 16.4% 65 or older, compared with 11.4% in 1970.

"Many of the towns are caught in a cycle of blight and degradation," Swenson told me. "They don't necessarily have a Plan B."