New York CNN Business  — 

Elon Musk lost tens of billions of dollars last week. He made nearly all of that back in a single day, Tuesday, following a 20% rally in Tesla’s stock.

Musk added $25 billion to his net worth yesterday, bringing his total fortune to $174 billion according to Bloomberg Billionaires Index. It’s a stark reversal from last week, when he lost $27 billion following a broader sell off of tech stocks.

His net worth remained largely unchanged Wednesday with Tesla’s stock only slightly lower. Musk owns nearly 18% of Tesla’s shares.

Musk and Amazon (AMZN) CEO Jeff Bezos have been swapping places atop Bloomberg’s list of richest people in the world since January. Musk is still in second place, but only $6 billion behind Bezos. His net worth is $180 billion, with the Amazon (AMZN) honcho adding nearly $6 billion Tuesday.

Microsoft (MSFT) founder Bill Gates remains the third-richest person on the planet. He’s worth $137 billion.

Tesla’s stock gained 743% in 2020, propelling it to No. 5 on the list of most valuable companies on the stock market. And the stock continued to climb in the early weeks of of 2021, gaining another 25% to a record high close of $883.90 on January 26. The stock has fallen about 25% since then.

Even if Tesla’s stock continues to sink, Musk still stands to become much richer in 2021 and beyond.

He received four grants to buy 8.4 million Tesla shares each in 2020. Each of those was worth $4.5 billion at Friday’s closing price, after taking into account the $70 per share excerise price Musk will have to pay. Musk will probably receive three additional options grants this year, each as large and as lucrative as those he received in 2020.

Musk has not exercised any of his options. Executives typically exercise them when they are due to expire, or to free up cash. Musk has never sold Tesla shares.

Musk also is the largest shareholder at privately-held SpaceX. The company completed a new funding round in February. While it has not disclosed the details, numerous published reports say the $850 million that it raised increased the valuation of that company 60% to $74 billion.

– CNN Business’ Chris Isidore and David Goldman contributed to this report.