Private sector in China has become the third "engine" of the country's fast-paced economic growth behind the state-owned and collective economies, the National Bureau of Statistics has said. According to the second national census of basic work units in China, there were 1.32 million private enterprises in China by the end of 2001, making up 43.7 per cent of the country's total number of enterprises, director of NBS Zhu Zhixin said.