Bitcoin falls below $20,000 for the first time since mid-July.

Bitcoin fell below $20,000 on Monday as investors sold risk assets following the Federal Reserve's reaffirmation of its commitment to an aggressive tightening course.

According to Coin Metrics data, the world's largest digital currency fell 5% from Friday's closing to a low of $19,526 overnight, a level not seen since July 13. Ether fell to $1,423, its lowest level in a month, as did other major digital coins.