The richest industry(i assume you are refering to oil) averaged a 7.6% profit.
By comparison, if you throw out the dismal auto industry, all other industries in the US averaged a profit of 9.2%
Oil industries in the united states last year made about 1.5% less per dollar invested than the average industry.
here is one site, although google turns up alot more
http://www.usnews.com/articles/busin...-windfall.html
Oil prices are regulated by supply and demand, the same as all other industries, they dont have some "magical pull" that helps them make money. Its just their industry has the most demand currently. So they can make the most profit, even though their profit margin is below average.