Copper futures hit a twelve-year high in Shanghai on worries that supply of copper may fail to keep up with demand due to quick growth in the Chinese economy. China’s economy grew 9.5 percent in 2004, the record level in eight years, which is pushing demand for commodities including copper up.

``Rising prices for cash delivery pushed up futures prices,’’ said Li Ling, a trader at Shanghai Jinpeng Futures Co. in a phone interview from Shanghai. ``There is a degree of supply shortage and it can have a magnifying effect’’ on copper futures.

Prices were also propped by the supposition that the State Reserve Bureau can purchase 10,000 tons of copper after the front month contract expires on April 15. The State Reserve Bureau is a government agency that regulates supply of commodities.