The digital currency bitcoin vaulted to a new record high above $4000 on Saturday, boosted by strong Japanese demand on its way to multiplying its value fourfold this year.

Bitcoin traded as high as $4,000.93, more than 7 percent higher near $3,941 in Saturday dealings, according to CoinDesk.

The digital currency has now quadrupled in 2017, and is up about 40 percent in August alone. Bitcoin’s market value is now around $64 billion, up about $10 billion in the last week.

Bitcoin trade in Japanese yen accounted for nearly 46 percent of global trade volume, up from about a third a day ago, according to CryptoCompare. US-dollar bitcoin trade accounted for about 25 percent, according to CryptoCompare. Bitcoin trade in Chinese yuan and South Korean won accounted for about 12 percent each.

Bitcoin rose in the last week, mirroring gold’s climb amid a global selloff in stocks and bonds. Rising worries about North Korea’s nuclear threat have sent investors flocking to perceived safe-havens and alternative assets.

Analysts have also noted increased investor interest, especially from institutional investors, after bitcoin successfully survived an Aug. 1 split into bitcoin and bitcoin cash.

This week, Fidelity launched a feature allowing customers to also view their Coinbase bitcoin holdings. The currency also got a boost from Goldman Sachs, which in a report released this week said it is harder for institutional investors to ignore cryptocurrencies like bitcoin.