Most women are at their peak "hotness" in their early 20's. You want to get a man to commit, that's the age to find a potential husband.
The people at dating site OkCupid did an article The Case For An Older Woman; How dating preferences change with age, looking at statistics from their site:
As you can see, a man, as he gets older, searches for relatively younger and younger women. Meanwhile his upper acceptable limit hovers only a token amount above his own age. The median 31 year-old guy, for example, sets his allowable match age range from 22 to 35 — nine years younger, but only four years older, than himself. This skewed mindset worsens with age; the median 42 year-old will accept a woman up to fifteen years younger, but no more than three years older.Women in their early 20's have the maximum range of selection. Women approaching 40 have to settle for who's left.
From my experience and talking to all my friends:
Guys in their teens want chicks in their teens
Guys in their 20s want chicks in their teens and 20s.
Guys in their 30s want chicks in their 20s. See what just happened there?
Guys in their 40s want chicks in their 20s but might go for early 30s
Life hands young women all the cards, but time is not their ally. Many don’t seem to grasp that the time to get a nice guy who has his life/career in order....maybe not rich yet but good career path or grad degree.....is in their 20s. If they’re still knocking around with “exciting” bad boy types who are going nowhere and think they’re going to be able to settle down with that nice guy when they’re 32-33, they’re heading for disaster. I’ve seen it several times. They’re always shocked when they discover the guys who were pursuing them even 5 years ago are no longer interested.