Reading the variety of responses to this question, I'm reminded of myself 20+ years ago, out on a date with an older guy. We had a bottle of wine with dinner, and I read the label to see the vintage year, then asked him "What were you doing in 1979?" He thought a few moments, said, "Let's see, I had my farm, my son was a toddler, I remember carrying him around on my shoulders … Why do you ask?"
"1979 was the year I graduated high school."
At the time, I just thought it was amusing. Now that I'm reading all the 20-somethings' responses to your original question and I'm on the other side of that age equation, I realize that that probably wasn't the hottest question I'd ever asked on a date!
And despite the facts that I just acknowledged my age (to anyone who can add and make an educated guess about how old a high school grad would be), and I referred to myself as "old" in the topic name … I just don't *feel* that old. At least as long as I'm not comparing my 20-something-self with others' toddler-selves or elementary-age-selves.
Relative. It's all relative. Or maybe I should say "vintage."