Development Data Group, The World Bank. 2013. 2013 World Development Indicators Online. Washington, DC: The World Bank. Available at: http://data.worldbank.org/indicator
GDP is calculated at as the total value of all goods and services produced by residents of a country including any product taxes and minus subsidies that are not included in the value of output. Data is converted to current U.S. dollars using single year official exchange rates, though for a few countries where the official exchange rate is not reflective of the rate applied to actual foreign exchange transactions, an alternative conversion factor is used.