Bitcoin’s price has plunged nearly 40% since @jack’s tweet.

It seemed like a good idea back in November, when Square Cash, a peer-to-peer payments app that’s part of Square, said it was about to let users buy, sell, and hold the cryptocurrency. Square’s stock shot up 5% on the announcement, while bitcoin rose over 10%.

But, as any cryptocurrency trader will tell you, timing the bitcoin market is next to impossible. What seemed like a savvy move to embrace the future of finance in November looks a little less prescient today.

📬 Sign up for the Daily Brief

Our free, fast, and fun briefing on the global economy, delivered every weekday morning.