"In 88 poor countries for which we have data, in each and every one of the 88, the PPP for food shows that poor people can buy less food than you would expect from the PPP that the World Bank is using. The reason for this is obvious on reflection. It has to do with the fact that most foodstuffs are tradable commodities: basic foodstuffs, such as rice, flour and beans, can easily be conveyed across national borders and their prices will therefore roughly mirror the exchange rates among currencies."

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Car prices play a large role in calculating PPPs even while they play no role whatsoever in the consumption or consumption needs of the poor. And the prices of rice, bread and beans play a small role in calculating PPPs even though they play a huge role in meeting the consumption needs of the poor. So the World Bank's method of comparing and converting everything at general purchasing power parities into US dollars is highly distorting within an exercise whose purpose it is to determine whether households are or are not capable of meeting their basic consumption needs.

— Thomas Pogge