The Bureau of Labor Statistics has found that 20 percent of Americans 65 and older are still working, the highest proportion since the early 60s before Medicare was first introduced, according to Bloomberg. Citing another survey, this one from the Federal Reserve, Bloomberg noted that 27 percent of Americans, in fact, plan to keep working as long as they can, and 12 percent of Americans plan to never retire. 

Reasons for this are varied. Bloomberg said they can include not having enough money to retire, wanting to continue work because they like their jobs, employers giving them extra incentives to stick around, people generally living longer, and people growing less satisfied with retirement overall.