WUHAN -- More than 80 percent of China's processed import and export trade was contributed by foreign-invested companies, according to an industry association report released on Sept 27.

In 2010, the total trade volume of imports and exports by foreign-invested companies in China reached $970.9 billion, accounting for 83.9 percent of the total volume in China, according to the report, which was compiled and released by the China Chamber of Commerce for Import and Export of Machinery and Electronic Products.

The report was released at the China International Machinery and Electronic Products Expo held in the city of Wuhan in central China's Hubei province.

Foreign-invested companies have contributed an average of 81.57 percent of China's processed trade since 2001, according to Lu Jinyong, a professor from Beijing's University of International Business and Economics (UIBE).

By taking advantage of China's cheap labor, foreign-invested companies have managed to reap most of the profits in the import-export industry, Lu said.