2 U.S. men sit atop the $100 billion club

Bloomberg tracks the fortunes of some 2,800 billionaires. Of those, 145 are worth at least $10 billion, making them decabillionaires. Now the world contains two centibillionaires simultaneously. Microsoft Corp. co-founder Bill Gates, once the world’s richest person, has again eclipsed the $100 billion threshold, joining Amazon.com Inc.’s Jeff Bezos in the exclusive club, according to the Bloomberg Billionaires Index.