Bitcoin was still falling against the dollar on Friday after losing more than a fifth of its value in trade Thursday.
Bitcoin was down over 1o% to $911.78 at 11:40 a.m. GMT (6:40 a.m. ET), according to Markets Insider. That's down from over $1,100 earlier in the week.bitcoinMarkets Insider
Bitcoin surged in the weeks running up to Christmas, battled volatility in the run-up to New Year and first few days of 2017, before tanking Thursday.
The exact reasons for the currency's rise and fall are unclear, but some commentators have suggested that the rise was caused by Chinese investors looking to move their money out of China ahead of a rumoured further devaluation of the renminbi. This theory is backed up by moves in the renminbi Thursday that coincided with bitcoin's plunge. The renminbi rallied 2.6% against the dollar, posting its biggest two-day gains ever.
China's central bank on Friday also warned investors to exercise caution when investing in virtual currencies such as bitcoin and met with the representatives of a major bitcoin trading platform in China, BTCC, according to Reuters. That appears to have shaken confidence further.
Mati Greenspan, a senior market analyst at the trading platform eToro, said in an email on Friday morning, "We can see a huge correlation between the two currencies with the USD/CNH often acting days or even months ahead of Bitcoin."
But he added, referring to data from the People's Bank of China that caused the renminbi to spike: "If we drill down, we can see that the $150 plunge that we saw in bitcoin actually came hours after the PBoC's nuke."

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