A brief history of Bitcoin bubbles

It’s been a breakout year for Bitcoin. In 2020 a wave of interest from mainstream investors and institutions helped push the price of the virtual currency from $7,200 in January to above $29,000 on December 31 (and then on past $32,700 by early January 2021). But the innovative digital asset, maintained by a decentralized swarm of so-called miners, has a long history of volatility. Most observers expect some retrenchment of that rally sooner or later.

For insight into why (or maybe when) a slump is likely, it’s worth looking back at Bitcoin’s many “bubble” periods: stretches when the price increased dramatically in a short amount of time, then fell, in most cases, even more sharply. “Bubble,” of course, has negative connotations, implying popular delusions and the madness of crowds. But there’s a growing understanding that financial bubbles can also be generated by temporary overoptimism about real innovation that can still pay off in the long run. Examples of this include the British Railway Mania of the 1840s and the 1999 Dot-com bubble.

Supporters see Bitcoin’s history of volatility as just a matter of watching the world catch up, in fits and starts, with an inevitable future. Ten years of steady growth seems to have vindicated that view—at least for now. But the growing pains can be truly savage.

Below, a trip down Bitcoin’s memory lane.

Caveat: Many of the Bitcoin marketplaces (such as Mt.Gox) that established the historical prices cited in the following text no longer exist. Even at the time, it would have been hard to identify a single price in the very small, relatively illiquid market. For simplicity and consistency, this article primarily relies on 99bitcoins.com for prices from 2009 to 2012 and CoinGecko for prices from 2013 to the present.

Feb. 2011: The Great Slashdotting/Dollar Parity Day

The Peak: $1.06 (Feb. 14, 2011)

The Bottom: $0.67 (April 5, 2011)

The Bitcoin bull run that peaked in February 2011 was arguably the cryptocurrency’s first bubble, and tremendously significant for its evolution. It began as early as July 2010, when Bitcoin—then worth just pennies per coin—was first mentioned on Slashdot, a news aggregator popular with die-hard techies. That post first brought important developers including Jeff Garzik and Jed McCaleb to the project. Heightened interest then drove the price of a Bitcoin to one dollar on Feb. 10, 2011. That day became known as Dollar Parity Day, and triggered a second Slashdot post that brought further attention.

That basic cycle is still a major dynamic of the Bitcoin market: real technology or infrastructure advances drive the price higher, then the price itself generates further, less sustainable price growth.

June 2011: The Bump on Silk Road

The Peak: $29.58 (June 9, 2011)

The Bottom: $2.14 (Nov. 18, 2011)

The first truly wild Bitcoin bubble began with a June 1, 2011 article about the darkweb market Silk Road on now-defunct news site Gawker. The article described how illegal drugs could be purchased on a hidden website using Bitcoin. (Beliefs at the time that Bitcoin is untraceable turned out to be wildly incorrect.) Just as important, the article followed on the heels of several early Bitcoin exchanges opening, which made the token easier to buy. The combination of attention and access sent Bitcoin from $10 to nearly $30 in just a week. Then, setting a pattern, it slumped for months.

November 2013: A Thousandaire

The Peak: $1,127.45 (Nov. 29, 2013)

The Bottom: $172.15 (Jan. 13, 2015)

Just short of three years after breaking the barrier to dollar parity, Bitcoin zoomed on to another crucial threshold, cracking $1,000 in late November 2013. It didn’t last, and the price cratered nearly 50% by mid December. This bull run is notable for its relative stickiness: The Bitcoin price declined relatively gently over a little more than a year to a new bottom, then rode along that bottom for another year. Prices didn’t break $1,000 again for more than three years after the first time.

December 2017: The Widowmaker

The Peak: $19,665 (Dec. 15, 2017)

The Bottom: $3,164 (Dec. 15, 2018)

The most brutal and crazy of all Bitcoin bubbles so far, except it wasn’t really a Bitcoin bubble. Instead, 2017’s bull run was largely fueled by a wave of newly-minted “alternative” cryptocurrencies that made big promises.

More importantly, a novel process known as an Initial Coin Offering (ICO) allowed founders to sell their new offerings directly to the public. That created not just one speculative mania, but literally thousands that fed off of each other: One ICO’s purely speculative run-up would create FOMO—that is, fear of missing out—for the next. Bitcoin benefited from the frenzy, but its “dominance,” or share of the overall crypto market, fell off a cliff as interest in “altcoins” surged.

It all ended in tears, of course. A mere week after peaking, Bitcoin dropped more than 25%. Other cryptocurrencies plummeted even further. Longer term, many of the projects rolling out ICOs turned out to be brazen frauds, and ICOs have since been broadly and aggressively pursued by the U.S. Securities and Exchange Commission as illegal securities offerings.

To cite one example of how bloody things got, Japanese tech mogul Masayoshi Son, of SoftBank fame, is reported to have lost $130 million in the 2017 crypto bubble—and that was allegedly his personal money, not SoftBank’s.

This time, it’s…different?

Veterans of Bitcoin’s wild roller-coaster ride have argued that the current white-knuckle run-up is, in crucial ways, different. (Of course, we’ve heard this before.) They argue that the absence of ICOs has forestalled the worst excesses of scammers and their greedy marks, the U.S. COVID stimulus can be read as validation of the inflation-hedge thesis that is crucial to Bitcoin’s appeal as an investment, and the presence of regulated institutions and publicly-traded corporations throughout the crypto market has created an entirely new sense of normality.

But Bitcoin, it can’t be repeated enough, is still a speculative and risky asset. If history is any teacher (and it often is) there will be more than a few more steps backwards on Bitcoin’s journey to the moon.

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This story was originally featured on Fortune.com