Monday was Bitcoin Pizza Day, the anniversary of the day in 2010 when developer Laszlo Hanyecz paid 10,000 bitcoins for two pizzas in the online currency's first recognized transaction. The same amount of bitcoins would be worth around $22.5 million now. The currency, which sank to $443 a year ago, is up more than 65% so far this month and has been soaring to record highs, passing $2,000 for the first time over the weekend and breaking through the $2,100 and $2,200 marks on Monday, reports CNBC, which notes that a $100 investment in bitcoins exactly seven years ago would be worth more than $75 million at the $2,251 price it reached Monday.
Analysts say several factors are behind the steep rise in the price of the currency, including political uncertainty worldwide and the ironing out of technical issues. Japan has also given bitcoins a big boost with new legislation allowing retailers to accept the currency. "The Japanese have caught the bitcoin bug and inefficiencies across markets are being exposed," CryptoCompare founder Charles Hayter tells Business Insider. But other "crypto-currencies," including Ethereum and Ripple, have been rising even faster than bitcoin, leading analysts to warn that a bubble appears to be developing, the BBC reports. (Read more bitcoin stories.)