He usually publishes the result of his studies on the Quarterly Journal of Applied Mathematics and Mechanics (http://www3.oup.co.uk/qjmamj/)
... 29.9% from 25 to 44, 23.8% from 45 to 64, and 7.9% who are 65 years of age or older. The median age is 35 years. For every 100 females there are 95.1 males. For every ...