Meta’s shares plummeted 23% in after-hours trading on Wednesday, after the company reported weak quarterly revenues and profits, which fell below analyst expectations. Meta executives blamed the shortfall, in part, on Apple’s new privacy rules on iOS, which the company introduced last October. The rules have crimped Facebook’s ability to serve ads.  

Meta also reported that Facebook’s daily active users had declined for the first time ever, dropping by about half a million over the previous quarter. The fall spooked investors, who worry that Meta and its fleet of social media apps are losing ground to younger rivals like Snap and TikTok, which dominate the Gen Z market.

Zuckerberg, who owns a 13% stake in Meta, saw his personal wealth collapse in line with his company’s. As markets opened Thursday, Zuckerberg’s net worth hit a low of $92 billion, tanking from $120.6 billion the day before. According to Bloomberg, the $29 billion crash dragged Zuckerberg out from the ranks of the world’s 10 richest people for the first time since 2015.

The Facebook founder’s single-day loss is the second largest in history. Last November, Tesla CEO Elon Musk lost $35 billion in net worth after he tweeted plans to sell 10% of his company shares. Tesla’s stock plummeted 12% as investors rushed to get ahead of the CEO’s selloff. But Musk remains firmly placed as the world’s wealthiest man, with a net worth of $231 billion.

According to the Bloomberg Billionaires Index, Zuckerberg’s losses dropped the 37-year-old CEO from the world’s seventh-richest man to No. 11, falling behind Mukesh Ambani, the chairman of Indian telecom conglomerate, Reliance Industries.

The rest of the top 10 wealthiest men (they are all men) remained largely in place as all of the leading billionaires—with the exception of Warren Buffett—suffered billion-dollar losses this year. Buffett, according to Bloomberg, is actually up $5.12 billion since the year began and ranks seventh on the wealth chart—where Zuckerberg used to be.

Ambani’s place among the world’s 10 wealthiest men was short-lived, however. On Thursday, Zuckerberg’s fortune continued to dwindle as Meta shares extended their downward trend and dropped 3%, but Reliance suffered a 3% selloff that same day, too. Ambani, who owns roughly 46% of Reliance shares, felt that 3% drop more than Zuckerberg felt his.

According to Bloomberg, Ambani’s net worth is now $89.2 billion—just below Zuckerberg’s new low of $89.6 billion, placing the Meta CEO at No. 10 in the pile.