As of 2015, Bill Gates, an American, is the richest man in the world, worth $79 billion. Carlos Slim, from Mexico, ranks second at $77 billion. Another American, Warren Buffet, rounds out the top three, at $72 billion.
The 50 richest people in the world are all billionaires, ranging from about $18 billion to approximately $86 billion. Sources disagree on the exact ranking and estimations, but according to Forbes, Microsoft founder Bill Gates ranks at number one for the 16th time in 21 years. Two women are in the top 10: Alice and Christy Walton of the Wal-Mart family fortune. There are only seven women on the list of the top 50. They include Jacqueline Mars of the Mars candy company; Laurene Powers Jobs, widow of Steve Jobs; Anne Cox Chambers of Cox communications; and Abigail Johnson, the president of Fidelity Investments. Mark Zuckerberg of Facebook, age 30, is the youngest billionaire on the list, ranking at number 11.
Forbes uses reporters across the globe to make estimates based on stock prices and exchange rates from around the world, and ranks wealth according to assets, and accounting for debt. Forbes' list has been published every March since 1987, but it does not include royalty or dictators whose wealth is based on or includes their possessions.