If you go the Dept of Labor link that Jumper gave us you will see how they came up with the money we make. It is based on a 40 hour week so if you make $70 and hour they say you will make $145,000 a year because we all work 40 hours a week and credit 160 hours a month...right?
Funny how one government agency, Dept of Labor, has not idea of the duty and work restrictions another agency, Dept of Trans, has on us.