As of this month, the unemployment rate is now lower than it was at any point during Ronald Reagan's administration:
That said, the labor force participation rate has fallen since Reagan's day. That's mostly about population aging — there are a lot more retired people now than there used to be — and a little bit about more people being in college, but that doesn't fully explain it. The labor force participation rate of "prime-aged" men between the ages of 25 and 55 has been steadily declining for decades, and in the past 10 years the participation rate for prime-aged women has fallen slightly as well.