Musk's fortune to break US$400bn in 2025, Tesla (TSLA.US) becomes a "drag" on his success in the business world.

Elon Musk's net worth fell below $400bn for the first time in two months as the price of Tesla (TSLA.US) plunged.

Tesla's shares have dropped 27% since hitting a record high in mid-December, when investors hoped Mr Musk's close ties with US president Donald Trump would boost the company's stock. Mr Musk's wealth peaked at $48.64bn on December 17, according to the Bloomberg Billionaires Index, with Tesla's shares and options accounting for more than 60 per cent of his fortune.

Last week was the worst week for Tesla since early October, with the stock falling 11 per cent after the company reported disappointing monthly deliveries. In Germany, Tesla's deliveries fell 59 per cent to a record low for 2023, while in China, Tesla's sales fell 11.5 per cent year-on-year.

Tesla fell 3 per cent to $350.73 on Monday, its fourth consecutive day of losses.

Mr Musk's political transformation was a key driver of the stock's rise after the US election. Since Mr Trump took office, Mr Musk has led cost-cutting efforts at the US Department of Energy.

However, investors' hopes that the Trump administration would push Tesla forward by changing the tax credits for electric vehicles and formally setting standards for autonomous driving technology have not yet been realised.

Ben Kallo and Davis Sunderland, analysts at Robert W Baird, wrote in a report on February 4 that Mr Musk viewed full self-driving as "the true value of Tesla", and added that they were now less enthusiastic about the company's autonomous taxi business after it withdrew its sales guidance when reporting fourth-quarter results.

While Tesla shares still account for the largest portion of Mr Musk's $39.46bn net worth, the recent drop in the stock — combined with record fundraising at some of Mr Musk's other companies, including xAI and SpaceX — means the carmaker's contribution to his wealth has declined relatively. Mr Musk's 42 per cent stake in SpaceX is currently worth $136bn.

Mr Musk also leads an investor consortium that has made an offer to buy OpenAI, the company behind ChatGPT, for nearly $95bn, according to reports. Sam Altman, chief executive of OpenAI, rejected the offer on Mr Musk's X social media platform.