Mayor Bloomberg won’t have to go to work after he leaves City Hall in January — he added another $6 billion to his net worth this year.
But Bloomberg, with $31 billion, remains only the 10th-richest American, according to Forbes’ annual list of the top 400, because his fellow billionaires also saw their wealth balloon.
Bloomberg was worth a mere $19.5 billion two years ago. His nest egg had plummeted during the recession from $20 billion in 2008.
Forbes didn’t detail how the mayor’s bankroll expanded but his prime source of wealth has been an 85 percent stake in his media/financial conglomerate, Bloomberg L.P.
Bloomberg’s additional $6 billion was far from the record for 2013.
Holding on to the top spot, Bill Gates, added $6 billion to hit $72 billion; No. 2, Warren Buffett, added $12.5 billion, to hit $58.5 billion.
But thanks to Facebook’s bounce-back from its IPO, Zuckerberg is back at No. 20 after doubling his worth to reach $19 billion, according to Forbes.
You might pity Oracle’s Larry Ellison. His $41 billion fortune didn’t grow this year, according to Forbes. He was the only member of the top 10 who didn’t see his wealth increase.
David Koch continued to be the richest New Yorker, with $36 billion, the same amount at his Wichita-based brother, co-owner withhim of Koch Industries.
Rounding out the top 10 Americans are four heirs of Wal-Mart founder Sam Walton. They stayed in sixth through ninth places, just ahead of Bloomberg.
Of the 400 richest Americans, 314 saw their nest egg grow, Forbes said.
“Basically, the mega rich are mega richer,” said Forbes Senior Editor Kerry Dolan.
Bloomberg, who founded his firm in 1981, is among the 273 members of the list who can be considered are self-made billionaires, rather than inheritors of a fortune.