Bitcoin Surges Past $5,300 to an All-Time High

What bitcoin bubble? On Thursday, the popular crypto-currency defied skeptics’ predictions and soared to a new all-time, past the $ 5,000 mark in the early morning and then climbing nearly another $ 400 higher through the day.

As of late afternoon ET, bitcoin sat around $ 5,320, which amounts to a one week gain of about 25% and a roughly 170% increase from its summer slump when the currency briefly fell below $ 2,000. Bitcoin began the year near $ 1000 and has been on a tear ever since.

Here is what the latest price run-up looks like in numbers. Here’s a chart from the trade publication Coindesk showing the price in the last week:

Meanwhile, here’s a 24-hour view compiled by the Winkelvoss twins, whose index is slightly more conservative because it doesn’t include data from more volatile foreign exchanges:

As is typically the case with bitcoin, it’s hard to point to a single explanation for the latest price spike, but likely factors include a surging interest from Japanese investors and signs that proclaimed crackdowns in Russia and China will not be as severe as feared.

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Other factors that may be spurring on bitcoin are a move by the large U.S. exchange Coinbase to let ordinary investors engage in day trading, and bullish notes from big banks like Goldman Sachs and even JP Morgan, a longtime bitcoin bull.

Today’s run-up also lifted the value of other digital currencies, including Ethereum and Litecoin.

Even as bitcoin grows more mainstream, there are no signs it has shed its famous volatility. For a longer-term view of recent bubbles and busts, see Fortune’s recent history of bitcoin crashes. Would-be investors may wish to consult our primer on $ 5,000 bitcoin, while skeptics can check out our guide to shorting it.

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