On a crisp morning in mid-November, “Marketplace” host Kai Ryssdal stepped onto a meandering forest trail in Cumberland County, Tennessee. Cumberland is a mostly rural county, sitting about midway between Nashville and Knoxville. 

“’I’ve been living here in Cumberland County for 13 years,” said local tour group organizer John Conrad as he showed Ryssdal one of the area’s many hiking trails. “I retired here, and just love it.” 

We came to Cumberland County to meet people like John. He’s a former engineer, 73 years old, and — like a lot of people you meet here — he’s not originally from Tennessee. But retirement has changed where and how he spends his time and money. 

For the past decade, he’s volunteered his time to help get public trails like this one built throughout the community. “It’s become something of an obsession,” he said. “Retirement’s a wonderful invention — I just love it.” 

With the coming wave of baby boomers reaching age 65, the United States of America is on the brink of a massive demographic shift. Prime-aged workers, which demographers typically define as 25-54 years old, are making up a shrinking share of the U.S. labor force. 

Here in Cumberland County, that shift is already well underway. About one-third of the population is 65 or older. That’s compared to less than 18% in the U.S. as a whole. 

As part of a new series, The Age of Work, about the aging U.S. labor force, “Marketplace” is exploring how Cumberland County’s high concentration of retirees has impacted the local economy. 

Click the audio player above to hear Ryssdal’s conversation with Conrad.