Regulation is in the air and investors are freaking out. Last week, it was Facebook that faced the wrath of angry government officials and lawmakers, following revelations of its mishandling of user data. Today, it seems President Donald Trump has it in for Amazon and seems eager for the e-commerce giant to be investigated for anti-competitive practices.

The market quickly reacted, kept reacting, and Amazon saw a huge dip. Its market capitalization shrunk from $724.73 billion to $692.93 billion, meaning the company lost $31.8 billion in value over the course of a day.

For perspective, CB Insights puts Airbnb’s entire valuation at $29.3 billion. WeWork and Palantir are both worth $20 billion. So Amazon lost more in value today than any of those three companies.

Jeff Bezos alone–who owns 78.89 million shares in the company–lost more than $1.6 billion today.

That’s a lot of money. Then again, the market has been wild these past few weeks, so it could just as easily rebound tomorrow.