China's craze for bitcoins has been well-documented over the past year, but a new report highlights just how dominant of a player the country is.

About 80 percent of bitcoin volume is now driven by the , according to data from Goldman Sachs. The U.S. dollar is the second most used currency for transactions, followed by the euro, the bank said in a new report.

The bank's findings correlate with data from Bitcoinity, a popular website used to track market data. A look at trading volume over the past six months reveals China's yuan accounted for 77 percent of total market share, compared with 19 percent for the greenback and just 1 percent for the euro.

China's high trading activity comes despite recent moves by the People's Bank of China (PBoC) to clamp down on the crypto-currency. The central bank banned financial institutions from bitcoin trading in December after warning that the currency was essentially a vehicle for speculation. Earlier in 2014, the PBoC also took measures to prevent bitcoin companies from gaining access to payment processors.

However, Goldman Sachs believes the mood is gradually improving: "However, in light of a somewhat stabilizing Bitcoin economy in China, a few payment processors have reemerged, such as BTC China's JustPay."