The central parity rate of the yuan, China's currency Renminbi (RMB), dropped 43 basis points Tuesday to 6.6775 per U.S. dollar, according to the data released by the China Foreign Exchange Trading System.

The yuan has picked up its strength against the U.S. dollars and seen increased volatility in the trading days since the People's Bank of China (PBOC), the central bank, announced on June 19 this year to increase exchange rate flexibility.

Based on Tuesday's central parity, the Chinese currency has strengthened against the U.S. dollar by 2.19 percent from the rate of 6.8275 per U.S. dollar that was set a day before the PBOC's pledge to increase flexibility.

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

The PBOC released the yuan's central parity rates against a basket of currencies -- the U.S. dollar, the euro, the Japanese yen, the Hong Kong dollar, the British pound and the Malaysian Ringgit.

The yuan's parity rate against the euro was set by the central bank at 9.2574 Tuesday, higher from 9.3215 on Oct. 11, the previous trading day.

The yuan's rate against 100 yen was 8.124 Tuesday, compared with 8.1276 on Monday.

The yuan's rate against the British pound was 10.6042, compared with 10.6311 on the previous trading day.

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

The central parity of RMB against the other five currencies is based on the central rate of RMB against the U.S. dollar of the same business day as well as the exchange rates of the five currencies against the U.S. dollar at 9 a.m. (0100 GMT) of the same business day in the international foreign exchange market.