The wealth of the 10 richest people in the world – a list dominated by US tech billionaires – increased by a record amount after Donald Trump’s victory in the presidential election, according to a widely cited index.

The Bloomberg Billionaires Index estimated that the world’s 10 wealthiest people gained nearly $64bn (about £49.5bn) on Wednesday, the largest daily increase since the index began in 2012.

Elon Musk, the world’s richest person, registered the largest increase with a $26.5bn addition to his fortune, which now stands at $290bn. The prominent backer of Trump’s campaign, benefited from a surge in the share price of Tesla, the electric carmaker where he is chief executive and in which he owns a 13% stake.