The Bitcoin roller coaster has had more peaks and valleys than usual over the past month. The price has soared to just under $72,000 and dipped asa low as $60,617, in a whiplash-inducing series of moves. Normally, that would be written off to the inherent volatility of cryptocurrencies, but this time around there’s a more solid reason: The Halving.

Sounding like the name of a pretty graphic horror film, the halving is actually an event that occurs every four years in the crypto space. And it’s often the catalyst for big gains.

Whether you actively invest in Bitcoin, own one of the ETFs that follow Bitcoin’s price or just have a curiosity about the crypto world, the halving might be an area of confusion. Here’s what you need to know about the event.

What is the halving?

A halving, at its core, is an event that occurs every four years, where the number of new coins going into circulation is reduced by 50%. That creates a scarcity as it reduces the pace that new Bitcoin can enter the market.

Bitcoins come into circulation as the result of miners, who use specialized PCs to discover block rewards, which then become part of the blockchain. In 2009, miners worked to unearth 50 Bitcoin every 10 minutes. As of the last halving, that was down to 6.25 Bitcoin every 10 minutes. After this event, that number will fall to 3.125 Bitcoin every 10 minutes.

When will the halving occur?

No one is precisely sure when the halving will occur, at least in terms of day and time. The best bet, as predicted by those who closely track this sort of thing, is between April 19 and 20. Halvings occur after 210,000 Bitcoins are mined. The Bitaps website tracks the number of Bitcoin in circulation. Once that hits 840,000, the 2024 halving will occur. (As of 2 p.m. ET, the number stood at 839,666, putting the event on track for a Friday night target.)

When was the last halving?

The third, and most recent, Bitcoin halving took place on May 11, 2020.

Will the halving spark a rally in Bitcoin’s price?

The 2020 halving did not cause much of a price fluctuation, at least not immediately. Around December of that year, however, the first big run-up in Bitcoin prices got underway, with prices jumping from under $9,000 at the halving to nearly $12,000 100 days later—and $60,000 by March of 2021.

This time around, though, Bitcoin hit a new record before the halving took place (largely because of the launch of Bitcoin ETF funds, which raised awareness and demand). Crypto enthusiasts are hopeful that awareness will increase even further as the buzz around this year’s halving keeps crypto in the news.

How many Bitcoin are in circulation today?

As of December 18, 2023, 19.57 million bitcoins have been mined.

How many more Bitcoin can be mined?

The total Bitcoin supply is capped at 21 million, which leaves about 1.45 million left to mine. It will be a while before those all make their way to market, though. With subsequent halvings, the final Bitcoin is not expected to be generated until 2140, though it might occur a bit earlier.