Bitcoin prices have reached a two-year high in anticipation of an event called the “halving.”

The halving occurs every four years and it cuts the rewards earned for mining bitcoins in half. This is likely the major force behind the increase in bitcoin prices. The event was designed to keep bitcoin from reaching its cap of 21 million too quickly.

Another factor that could be helping bitcoin prices go up is high trading for the virtual currency. 400,000 bitcoins worth $279 million were traded between Sunday and Monday afternoon. Bitcoin value reached $719 on Monday, reports The Wall Street Journal.

CoinDesk‎ noted that the increased bitcoins prices could also be partly caused by concerns that the United Kingdom could leave the European Union, an increased interest in blockchain and an higher demand for the virtual currency.

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