How rich is the richest man in the world? The answer keeps changing, because Jeff Bezos keeps getting wealthier.

Bezos, founder and CEO of Amazon as well as owner of The Washington Post, is already the wealthiest man in the world. But this week, his fortune grew by an astonishing $2.8 billion—yes, with a “b”—in a single day, Fortune reports, after Amazon’s stock price rose 2.5 percent.

The stock soar came as a result of the opening of Amazon Go, a cashier-less store based in Seattle. “The store, on the bottom floor of the company’s Seattle headquarters, enables shoppers to scan their smartphone with the Amazon Go app at a turnstile, pick out the items they want and leave,” CBS News explains. “By combining computer vision, machine learning algorithms and sensors, the online retail giant can tell what people have purchased and charges their Amazon account. If someone puts an item back, they aren’t charged.”

Bezos’ $2.5 billion gain brings his total net worth to its highest level ever, Fortune reports:

It’s a significant lead over the world’s second and third richest men, Bill Gates and Warren Buffett, who have net worths of $92.5 billion and $92.3 billion, respectively. Bezos’ 12-figure-fortune nominally makes him the wealthiest person since Forbes started tracking fortunes in 1982. If we factor in inflation, Bill Gates was richer back in 1999, when he briefly passed $100 billion — worth roughly $150 billion in today’s dollars.

(The Washington Post, it’s worth noting, did not report on this news; its most recent coverage of Bezos was to tout his recent $33 million donation for young immigrant “Dreamers” earlier this year.)

This nearly incomprehensible sum of money shines a light on America’s economic inequality, critics argue. Sen. Bernie Sanders, I-Vt., wrote in a Facebook post in response to the news of Bezos’ single-day wealth increase:

While Amazon’s CEO is the richest person in the world, thousands of Amazon employees are struggling to get by and relying on public assistance to make ends meet. Nobody should have more money than they could possibly ever spend especially while their employees are struggling to put food on the table. What we need is a society that reverses the egregious trends of income and wealth inequality we are seeing and allows working families to thrive.

Sanders is referring to a recent report by the nonprofit Policy Matters Ohio, which found that over 1,000 Amazon employees in Ohio were on food stamps in 2017. Additional reports of the poor labor practices inside Amazon warehouses and Whole Foods markets, recently purchased by Amazon, are also beginning to surface.

Bezos, meanwhile, is focusing his attention on perfecting voice-recognition software and teaming up with fellow mega-corporations Berkshire Hathaway and JPMorgan Chase to form an independent health care company to overhaul health care in the United States.

So to summarize: Jeff Bezos, the wealthiest man on the planet, currently owns a news outlet with more than 100 million readers; founded and controls an online store that accounts for 43 percent of all online retail sales and is more valuable than all brick-and-mortar retail stores combined; owns a new brick-and-mortar store, Amazon Go, that could spell the downfall of retail employees everywhere; is pioneering voice-recognition software that could pose security risks; founded an aerospace company, Blue Origin, that ultimately intends to launch commercial space flight trips but also makes rockets; invests in numerous smaller start-up businesses, including “collaborative robot technology,” “digital learning” systems and a company focused on “developing artificial general intelligence for robots.” Now he wants to get into health care.

“The health care system is complex, and we enter into this challenge open-eyed about the degree of difficulty,” Bezos said in a statement. “Hard as it might be, reducing health care’s burden on the economy while improving outcomes for employees and their families would be worth the effort. Success is going to require talented experts, a beginner’s mind, and a long-term orientation.”