Important works include:
Links: http://www.horatioalger.com/member/dur71.htm
... 18 to 24, 29.0% from 25 to 44, 24.2% from 45 to 64, and 12.7% who are 65 years of age or older. The median age is 39 years. For every 100 females there are 104.2 males. ...