The central parity rate of yuan, the Chinese currency, Friday retreated 54 points to 6.5930 against the U.S. dollar, according to the China Foreign Exchange Trading System.

China's central bank announced in June 2010 it would further reform the exchange rate formation mechanism to improve its flexibility.

On China's foreign exchange spot market, the yuan can rise or fall 0.5 percent from the central parity rate each trading day.

The central parity rate of the RMB against the U.S. dollar is based on a weighted average of prices before the opening of the market each business day.