A note on purchasing power parity and the choice of price index

The PPP argument states that the currencies purchasing power should be the same across countries for the same basket of tradable goods. We run a horse race among six different price indices to see which one yields higher PPP evidence, and, therefore, better fits this criterion. Using export unit values, WPIs, value added deflators, unit labor costs, normalized unit labor costs and CPIs for 16 countries from 1975 to 2002, unit root tests show that WPI was the index for which PPP evidence was found for the larger number of countries. No evidence of PPP was found for the ratio CPI/WPI.