Univariate studies of the hypothesis of unit roots in real exchange rates have yielded consensus point estimates of the half-life of deviations from purchasing power parity of between three to five years. However, least squares-based estimates of half-lives are biased downward. Accordingly, we...

This paper examines the persistence of shocks to the terms of trade, using annual data on 42 Sub-Saharan African countries between 1960-96. We find that the persistence of terms of trade shocks varies widely—for about half the countries such shocks are short-lived, while for one-third of the...

Consensus estimates put the half-life of deviations from purchasing power parity (PPP) at about four years (Rogoff, 1996). However, conventional least squares estimates of half-lives are biased downward. Accordingly, as a preferred measure of the persistence of real exchange rate shocks, this...