Unsurprisingly, the most popular major is economics. : If you want to make it into the billionaire's club, picking the right college major might be a good place to start. That's because for the richest people in America, the most common major selected was economics, according to a Forbes analysis of the billionaires who made the latest Forbes 400 list. Hedge fund manager Steve Cohen, Hewlett Packard Enterprise CEO Meg Whitman, and New England Patriots owner Bob Kraft all chose to major in economics as undergraduates, before launching successful careers.