Hong Kong - referred to officially as the "Hong Kong Special Administrative Region" by the Chinese government - was under British administration from 1842 until a transfer of sovereignty to the People's Republic of China in 1997. Today, the region operates with a great degree of autonomy under the Sino-British Joint Declaration, which provides for semi-autonomous status until at least 2047. Hong Kong's sovereignty is protected by the declaration except in areas regarding national defense and foreign relations, which are overseen by China's national government in Beijing. The region's status as China's wealthiest urban center is owed in large part to the nature of its highly capitalist economy, which boasts free markets, low taxation and government non-intervention. An important center for international finance and trade, Hong Kong - which lacks natural resources and has little arable land - operates via an economy dominated by services, which accounts for over 90 percent of the region's gross domestic product.