Jeff Bezos, already the world’s richest man, has gotten even wealthier recently—adding an eye-popping $10 billion to his net worth in less than two weeks. According to the Bloomberg Billionaires Index, Jeff Bezos’s net worth was $99 billion on New Year’s Day 2018. One week later, Bezos hit the $105 billion mark, making the Amazon founder and CEO richer than Microsoft founder Bill Gates had ever been, at least in nominal terms. As of the close of the stock market on Friday, Bezos’s net worth hit the $109 billion mark, according to Forbes.