There's been a reshuffling on the Forbes Billionaires list for 2016, as internet tycoons Mark Zuckerberg and Jeff Bezos make appearances among the magazine's top 10 for the first time.

Bill Gates still tops the list, published Wednesday, marking the third year the Microsoft founder has been ranked the richest person in the world.

But volatile stock markets and changing fortunes of oil and commodities made a difference in the net worths of many people — and 229 have slipped off the list altogether.

Forbes counted 1,810 billionaires worldwide this year, down from a record 1,826 in 2015. Their aggregate net worth was $6.48 trillion US, $570 billion US less than last year.

Facebook founder Zuckerberg zoomed up the list, from a ranking of 16 to No. 6, having added about $11 billion US to his fortune this year.

Facebook Zuckerberg

Facebook CEO Mark Zuckerberg added $11 billion US to his fortune in the past year, moving him up to No. 6 on Forbes' list of billionaires. (Associated Press)

Bezos, who founded, is also a newcomer to the top 10, coming in at No. 5.

There was also some jockeying for the top spots, with Carlos Slim, head of Mexican telecom firm América Móvil, slipping from second to fourth place after his fortune was hit hard by a falling peso and depressed stock prices.

  1. Bill Gates, $75 billion, Microsoft.
  2. Amancio Ortega, $68.2 billion, Zara.
  3. Warren Buffet, 63.4 billion, Berkshire Hathaway.
  4. Carlos Slim, $53.2 billion, América Móvil.
  5. Jeff Bezos, $48.9 billion,
  6. Mark Zuckerberg, $46.7 billion, Facebook.
  7. Larry Ellison, $45.2 billion, Oracle.
  8. Michael Bloomberg, $40 billion, Bloomberg.
  9. Charles Koch, $41 billion, Koch Industries.
  10. David Koch, $41 billion, Koch Industries.

The U.S. has 540 billionaires, more than any other country. It's followed by mainland China with 251 billionaires, 38 more than a year ago.