Authors:

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.

Source: www.truth-out.org
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