Inflation and Exchange Rates: An International Examination of Relative Purchasing Power Parity

Abstract

Purchasing power parity (PPP) is an old and controversial proposition in economic literature. It is based on the law of one price, which argues that, after adjusting for the exchange rate, domestic and foreign price levels are equal. The relative version of PPP argues that exchange rate changes depend on the differential between domestic and foreign inflation rates. The absolute PPP version is based on restrictive assumptions that prevent it to hold in the short run. However, several studies support the validity of the relative PPP proposition in the long run. It is often observed that countries with persistently high inflation experience weak currencies. Our empirical testing using impulse response functions derived from a VAR model for eight countries provide mixed results. In six out of eight selected countries, relative PPP is supported by data in the long run.