The central parity rate of China's currency Yuan broke 7.5 for the first time, opening today at 7.4938 to one US dollar, according to the Chinese Foreign Exchange Trading System.

The yuan has appreciated 8.22 percent from the central parity rate of 8.11 when the People's Bank of China announced exchange rate reform eliminating the fixed link with the US dollar on July 21, 2005.

At a central bank conference on Tuesday, the Chinese monetary policy maker said it would strengthen financial control efforts to improve the valuation mechanism of the renminbi exchange rate.

However, in the meantime, Hank Paulson, the financial chamberlain of the United States, issued new complaints about the lumbering yuan's appreciation, saying the yuan is significantly undervalued considering China's trade surplus and production basics.

It is likely Paulson failed to consider potential financial instability and risk of increased unemployment.