[carbon8]

Also, from a Kauffman Foundation report:

"The average and median age of U.S.-born tech founders [of companies that have more than $1 million in sales, twenty or more employees, and company branches with fifty or more employees] was thirty-nine when they started their companies. Twice as many were older than fifty as were younger than twenty-five."

http://www.kauffman.org/what-we-do/research/2009/04/educatio...