Elon Musk, once worth as much as US$340 billion, has been displaced as the world’s richest person by Bernard Arnault.

Musk, 51, has seen his fortune tumble by more than US$100 billion since January to US$163.6 billion, according to the Bloomberg Billionaires Index. That’s less than the US$170.8 billion net worth of Arnault, 73, whose wealth largely derives from his 48 per cent ownership of fashion giant LVMH.

Musk’s fall from atop the rankings — the first time that’s happened since he was No. 2 in September 2021 — caps a tumultuous year for the frenetic billionaire. He shocked the world in April with his offer to take Twitter private for US$44 billion, in a brazen display of how the wealthiest individuals could wield their massive fortunes.

But his agreement coincided with the Federal Reserve and other central banks embarking on their most aggressive round of monetary tightening in a generation, slashing the valuations of high-flying companies like Musk’s Tesla Inc. The electric carmaker’s stock is down more than 50 per cent this year.

Tesla fell 4.1 per cent on Tuesday to US$160.95, the lowest closing price since November 2020.

Musk tried for months to get out of the Twitter deal, but failed. He offloaded more than US$15 billion in Tesla shares — about US$8.5 billion in April, then another US$6.9 billion in August — to raise enough cash to fund the purchase.

Once he finalized the Twitter acquisition in October, the Bloomberg wealth index knocked US$10 billion from his fortune, reflecting that shares of similar businesses have slumped since he made his bid.

Musk has pledged to turn around the social-media platform, but he faces several challenges — some of his own making. He blasted Apple Inc. and threatened to withhold Twitter from its App Store at a time when other companies were already pulling their advertising from the site. 

Meanwhile, Twitter is poised to face annual interest costs that exceed a measure of its earnings for all of 2021. Musk’s bankers are considering providing him with new margin loans backed by Tesla stock to replace some of the high-interest debt he layered on Twitter, Bloomberg News reported.

As Tesla’s stock price slides, Musk’s stake in Space Exploration Technologies Corp. has become an increasingly important part of his fortune. It’s worth US$47 billion, based on the June funding round that valued the private company at about US$125 billion.

SpaceX is offering to sell insider shares at a price that would raise the closely held company’s valuation to about US$140 billion, Bloomberg News reported this week, citing people familiar with the matter. That higher value could lift his net worth, but it’s not yet being used by Bloomberg’s wealth index because it’s unclear whether any shares have traded so far and the size of the transactions.

Arnault, the new richest person in the world, is drama-free in comparison to Musk.

Arnault has long been a mainstay near the top of the wealth rankings, but his fortune never grew at the exponential pace of US tech billionaires. Now his empire is holding up while Mark Zuckerberg, Jeff Bezos and Alphabet Inc.’s Larry Page and Sergey Brin see their wealth hammered by rising interest rates.

Paris-based LVMH Moet Hennessy Louis Vuitton’s designer apparel, fine wines and retail business have benefited from pent-up demand unleashed when Covid-related shopping and travel restrictions were lifted in most countries. Arnault’s brands cater to the affluent — from Christian Dior and Fendi to jewelers Bulgari and Tiffany & Co., and champagne house Moet & Chandon.