Austin, Texas - How the mighty have fallen! Elon Musk is no longer the richest man in the world.

Musk (49) lost $27 billion of personal net worth as Tesla shares dropped this week. At one point, he sank to third place on Forbes' billionaire ranking list, which tracks billionaires' wealth in real-time every five minutes during business days.

With just one billion dollars separating them, Musk duked it out with Bernard Arnault (72), who ended the trading day on Friday with $149 billion in his pocket.

The Frenchman owns the luxury group LVMH which includes famous brands like Louis Vuitton and Moët & Chandon.

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But Musk eventually ousted Arnault with $150.4 billion – a razor-thin lead.

In January, Musk toppled Amazon founder Jeff Bezos (57) from his throne as the world's wealthiest person, a position that Bezos had held since October 2017.

With a fortune of $177.6 billion dollars and Musk's sudden drop this week, Bezos currently leads the list again.

This is not the first time the South African has seen low depths – in 2020 Musk was only 31st on the world's richest list.

The CEO and tech entrepreneur's rapid rise and fall has a single reason: Tesla. The stock market share price of the electric car manufacturer has risen by an incredible 743 percent since January 2020.

The environmental car company hopes that the new Biden administration's commitment to climate change will further increase Tesla's profits.

Musk has also committed $100 million of his own money in helping to reduce carbon emissions.

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He personally owns 21% of Tesla's shares, so he benefited from the company's stock market surge more than any other investors.

But since last year's high, Tesla has recently been trading much lower. In January 2021, a share cost almost $900, while on Friday the price had plummeted to nearly $600.

Since Monday, the 49-year-old has lost $27 billion, Bloomberg has calculated.

With his other ventures in space exploration and investments in Bitcoin, the entrepreneur has his hands in many pots that could bring him back up to the top spot.