Instability in short-run adjustments to purchasing power parity: results for selected Latin American countries

According to the theory of purchasing power parity (PPP), there is a tendency toward equalization of different countries' price levels in common-currency terms. However, even assuming that a long-run PPP relationship exists, its relevance for policy makers in less developed countries (LDCs) will depend not only on the average speed of adjustment toward this relationship but also on the variability of such short-run adjustments. We present evidence of extreme volatility in adjustments toward PPP for four Latin American countries, based on time-varying-parameter estimates of error-correction models.