Image copyright Getty Images Image caption Bill Gates has topped the Forbes list for the fourth straight year

Microsoft founder Bill Gates again tops Forbes' list of the world's richest people, in a year when the number of billionaires rose 13% to 2,043.

According to the magazine's annual rich list, Mr Gates' fortune rose to $86bn, from $75bn, followed by investor Warren Buffett, up $14.8bn to $75.6bn.

It was bad news for US President Donald Trump, who slipped 220 spots to 544 and must now rub along on just $3.5bn.

Forbes said the $1bn fall in his wealth was due to the slow US property market.

There were 183 tech billionaires on the Forbes list, with a combined $1tn in wealth. The list is dominated by US billionaires.

Others in the top 10 included Amazon founder Jeff Bezos, who moved up to number three with the biggest gain of any person on the planet, a $27.6bn rise in his fortune of $72.8bn.

Facebook founder Mark Zuckerberg was number five and Oracle co-founder Larry Ellison was number seven.

The global population of billionaires, now put at a record 2,043, marks the biggest annual increase in the 31 years since the magazine began compiling the list.

The number of US billionaires on the list was 565, which Forbes attributed to the recent stock market surge since Mr Trump's November 2016 election.

China was second with 319 billionaires, and Germany was third with 114.

Forbes' top ten:

Bill Gates (Microsoft co-founder): $86bn

Warren Buffett (US investor): $75.6bn

Jeff Bezos (Amazon founder): $72.8bn

Amancio Ortega (Inditex founder): $71.3bn

Mark Zuckerberg (Facebook founder): $56bn

Carlos Slim (Mexican magnate): $54.5bn

Larry Ellison (Oracle co-founder): $52.2bn

Charles Koch (US businessman): $48.3bn

David Koch (US businessman): $48.3bn

Michael Bloomberg (Bloomberg founder): $47.5bn

The number of women on the list rose to 227 from 202, giving them a collective net worth of $852.8bn. For the second year running France's Liliane Bettencourt, the L'Oreal cosmetics heiress, was the world's wealthiest woman with a $39.5bn net worth.

Most of the richest women inherited their fortune, Forbes said. But the list also contained 15 new "self-made" women, mostly from Asian countries, including Vietnam's Nguyen Thi Phuong Thao of budget airline VietJet air.

Trump's tumble

Forbes attributed the US president's slide down the list to the sluggish Manhattan property market, which is responsible for a disproportionate amount of his wealth.

Image copyright AP

"Forty percent of Donald Trump's fortune is tied up in Trump Tower and eight buildings within one mile of it," Forbes said. "Lately, the neighbourhood has been struggling - relatively speaking."

The magazine also said that his wealth was hit by $66m in political spending on his successful presidential campaign, as well as $25m to settle litigation he allegedly ripped off students at Trump University.

Mr Trump would also have missed the big Wall Street rally following his election, assuming he sold off all of his shares during last year's campaign, the magazine said.

But not all of the trends were negative for Mr Trump.

The magazine estimated the worth of the Mar-a-Lago resort in Florida rose $25m due to post-election exposure.

Forbes list facts: