Jeff Bezos stands out at the top of the wealthiest people in the world. Something to note is that Mark Zuckerberg at fifth place is only 33 years old and the next youngest is Jeff Bezos at 54.
Top four biggest sources of billionaire wealth is from the USA. Though Koch Industries is the top source of wealth, it is split between two brothers. Four of the top ten are IT based companies and all four of them are from the USA.
Business environment in the USA seems most favorable to top billionaires with it having almost 72% of the wealth of the top 10 billionaires and the other three countries having around 9% each.