Significant transformation of economic activities has taken place in Hong Kong in the past two decades. Hong Kong's manufacturing industry has declined substantially relative to the service industry in terms of the employment and contribution to GDP. Hong Kong has emerged as a center of services, mainly manufacturing-related producer services. While growth of producer services is expected for most advanced economies, Hong Kong's transformation from an industrialized city to a center of manufacturing-related services has been dramatically sped up by the opening-up of the Mainland Chinese economy in the past two decades. In addition to its relocation of manufacturing to the mainland China, Hong Kong has played an increasingly important role of intermediary for trade between Mainland China and the world market.