计算数据来源:World Bank, World Development Indicator 2011; Angus Maddison, Statistics on World Population, GDP and Per Capita GDP, 1—2008 AD, 2010, et/MADDISON/oriindexhtm;Population Division of the Department of Economic and Social Affairs of the United Nations Secretariat, World Population Prospects: The 2010 Revision, esaunorg/unpd/wpp/indexhtm