The Hong Kong Special Administrative Region (SAR) and the People's Republic of China are often each spoken of as the most important trade partner for the other, yet this assumption must be refined because included in the Hong Kong trade statistics is trade between China and other countries that flows through Hong Kong. Moreover, Hong Kong's foreign trade is difficult to measure because the relocation of a large number of Hong Kong industrial firms to mainland China, in particular the province of Guangdong, has significantly transformed the import/export structure.

Prior to the open …