BEIJING, May 21 (Xinhua) -- The central parity rate of the Chinese currency renminbi, or the yuan, weakened 2 basis points to 6.8990 against the U.S. dollar Tuesday, according to the China Foreign Exchange Trade System.

(File photo: VCG)

In China's spot foreign exchange market, the yuan is allowed to rise or fall by 2 percent from the central parity rate each trading day.

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