Forbes lists first 1000 billionaires only. But there are more than 1000 billionaires. Maybe 2000 or more (not sure). I had a argument with a person who claimed to have earned 6% profit per month for some 11 years. There is a possibility there are some hidden billionaires in this world because some people say there are plenty of industries that provide high income (10% or 30% per month) for a long time. Online forums have many many stories who claim to earn high profits.