1. Learning a new language. Your ability to do it peaks when you're around 7 or 8.
2. Remembering people's names . . . 22 years old.
3. Finding someone to marry . . . 26 years old.
4. Running a marathon . . . 28 years old.
5. Playing chess . . . 31 years old.
6. Remembering people's faces . . . also 31 years old.
7. Winning a Nobel Prize . . . 40 years old. That's when the average winner has done it.
8. Making your peak salary at work . . . 39 years old for women, and 48 for men.
9. Doing math in your head . . . believe it or not, around 50 years old.
10. Having a strong vocabulary . . . late 60s or early 70s. There's a bit of a decline after that.
And in general, our happiness level peaks at 23, and again at 69.