Mark Zuckerberg just became the sixth-richest person on Earth.

The Facebook Inc. founder saw his fortune rise $5.5 billion in early trading Thursday as the world’s biggest social network delivered another quarter of record revenue. That gives the 31- year-old a net worth of about $47 billion, enough to surpass the $45.3 billion holdings of brothers Charles and David Koch, according to the Bloomberg Billionaires Index.

Facebook reported on Wednesday that fourth-quarter sales were up 52 percent to $5.84 billion and net income had more than doubled to $1.56 billion from a year earlier. More than 1.59 billion users are now logging on every month, according to the company.

Thursday’s surge turned a year-to-date decline of more than $4 billion for Zuckerberg into a $1.2 billion gain for the year and pushed him above the Kochs, whose industrial holdings have been hit by lower oil prices.

The five billionaires that remain above the tech entrepreneur in the ranking -- Bill Gates, Amancio Ortega, Warren Buffett, Jeff Bezos and Carlos Slim-- have lost a combined $24 billion so far this month through Wednesday trading as global equities slump amid dimming investor expectations of global growth.

Billionaire Net Worth Change YTD 

Bill Gates $77.9 billion -$5.9 billion

Amancio Ortega $70.2 billion -$2.7 billion

Warren Buffett $59.1 billion -$3.2 billion

Jeff Bezos $51.9 billion -$7.8 billion

Carlos Slim $47.8 billion -$4.5 billion

Mark Zuckerberg $47.0 billion +$1.2 billion

Zuckerberg is now one of only three billionaires among the 20 richest people on Earth to see an increase this year, according to the Bloomberg index, a daily ranking of the world’s 400 richest people. The billionaires had a combined net worth of $3.7 trillion as of Jan. 27, a 14 percent decline from their peak of $4.3 trillion on May 18, 2015.