billionaire

It came as the Microsoft co-founder announced he would make a $20bn (£17bn) donation to his philanthropic fund.

The world's fourth richest man said he had an "obligation" to return his resources to society.

Mr Gates first pledged to give away his wealth in 2010 but his net worth has more than doubled since then.

He is currently worth $118bn, according to Forbes magazine, but that will fall significantly after his donation in July to the Bill & Melinda Gates Foundation, the charitable fund he set up with his ex-wife in 2000.

The pop star is worth $1.7 billion (£1.2 billion), with an estimated $1.4 billion coming from the value of her Fenty Beauty cosmetics company.

The rest of her fortune mostly comes from lingerie company, Savage x Fenty, worth an estimated $270 million, and her earnings from music and acting.

She is second only to Oprah Winfrey as the world's richest female entertainer.

Rihanna - whose real name is Robyn Fenty - launched Fenty Beauty in 2017 in a partnership with luxury goods company LVMH.

He was 87.

The founder of the Las Vegas Sands casino company, Adelson was known for his support of conservative causes and Israel.

He was a significant backer of US President Donald Trump and Israeli Prime Minister Benjamin Netanyahu.

His death was caused by complications related to his treatment for non-Hodgkin's lymphoma, the Las Vegas Sands company said in a statement.

In a statement, former US president George W Bush said he mourned the passing of a "friend".

This week, the eccentric billionaire - number nine in last year's Bloomberg Billionaire's List - revealed in a documentary broadcast this week on Swedish television that he buys his clothes at flea markets to save money, according to Agence France Presse.