The 2005 Global Purchasing Power Parities and Real Expenditures
This provides information on gross domestic product (GDP), GDP per capita, household consumption, collective government consumption, and capital formation for 146 economies. These estimates are derived from PPPs based upon national surveys that priced nearly 1,000 products and services.
This is the world's largest statistical initiative. It produces internationally comparable price levels, economic aggregates in real terms, and Purchasing Power Parity estimates. The ICP uses a series of statistical surveys to collect price data for a basket of goods and services. For meaningful inter-country comparisons, the ICP considers the affordability and price level of necessities and luxuries, which exchange rates ignore.
Surveys are held every three to five years, depending on the region. The data collected are combined with other economic variables from countries’ national accounts to calculate Purchasing Power Parities or PPPs, a form of exchange rate that takes into account the cost and affordability of common items in different countries, usually expressed in the form of US dollars.