The economy is doing fine, so I would have to say it's the "Boomers" (of which I am one). Many of my age cohort have NOT made the necessary savings/investment choices to have a sufficient retirement "nest egg.
I do have such a retirement fund, and could retire tomorrow. I choose not to, because I've found a job niche that I really enjoy. Someday that may pall, and I will actually "retire"--but, even then, I'll probably work at "something" (at least part time).
I wonder if any private schools could use a part-time chemistry/science teacher???
Depending on where you live, part-time teaching may be an option. I sub several times a month. I could do it every day, but I only do it for one school. There are some schools I would never even consider.
Don't know the size of your town(?) but you could most likely make some very nice pocket change as a tutor or sub teacher.
Imagine the tremendous boost to this country if all public school and many private school teachers were suddenly replaced by semi-retired older people. People who have a clue, and can also spell and do arithmetic. They'd vote the NEA out of existence in a heartbeat.
We could cut public school costs and property taxes in half AND increase the test scores for the first time if we hired retirees to teach in public schools for 5 years or more after retirement.