It’s been a long few weeks since the cryptocurrency crowd was partying in Miami.

Coinbase Global Inc. founder Brian Armstrong had a personal fortune of $13.7 billion as recently as November and about $8 billion at the end of March. That’s now just $2.2 billion, according to the Bloomberg Billionaires Index, after a selloff in digital currencies from bitcoin to ether triggered a precipitous decline in the market value of Coinbase, the largest U.S. cryptocurrency exchange.

The firm’s shares have tumbled 84% since their first day of trading in April 2021, closing Wednesday at $53.72 after the company warned that trading volume and monthly transacting users were expected to be lower in the second quarter than in the first.