Bitcoin has hit a 20-day low, sinking to $44,069.29 at 17:08 GMT, continuing its downward trend of the past week, according to trading data at CoinDesk.
Since hitting its all-time high of $58,332.36 last week, the world's most popular cryptocurrency has seen its value plunge nearly 24%.
Earlier this week, US Treasury Secretary Yellen named bitcoin "an extremely inefficient way of conducting transactions", slamming it as an "extremely volatile" and "highly speculative asset" that is rarely used for financial transactions in addition to its "staggering" consumption of energy.
For most of February, bitcoin reported record-breaking growth after the electric vehicle company Tesla confirmed a $1.5 billion investment in the cryptocurrency.
Bitcoin is currently the biggest digital currency in terms of market capitalisation. It was launched in 2009 after being invented a year prior by Satoshi Nakamoto, whose actual identity remains unknown.
