The paper describes six different methodologies that have been used to assess the equilibrium values of exchange rates and discusses their limitations. It applies several of the approaches to data for the United States as of 2006, illustrates that different approaches sometimes provide...

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...

This paper uses three methods to assess movements of real exchange rates in the ECCU over time. First, the purchasing power parity hypothesis is tested and then used to provide a benchmark for equilibrium real exchange rates in the region. Second, a fundamentals-based equilibrium real exchange...

This paper examines whether the real exchange rates of commodity-exporting countries and the real prices of their commodity exports move together over time. Using IMF data on the world prices of 44 commodities and national commodity export shares, we construct new monthly indices of national...

This paper examines whether deviations from PPP are stationary in the presence of nonlinearity, and whether the adjustment toward PPP is symmetric from above and below. Using alternative nonlinear models, our results support mean reversion and asymmetric adjustment dynamics. We find differences...

This paper introduces a time-varying threshold autoregressive model (TVTAR), which is used to examine the persistence of deviations from PPP. We find support for the stationary TVTAR against the unit root hypothesis; however, for some developing countries, we do not reject the TVTAR with a unit...

This Selected Issues Paper and Statistical Appendix for Niger are discussed. The Nigerien economic outlook has been improving since 1999. After a long period of decline in per capita income, growth accelerated through 2007, attaining an annual average of 4 percent, or about 1 percent in per...

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 external sustainability and competitiveness of Benin’s economy. Balance of payments flows suggest Benin’s external position is sustainable. Large trade and current account deficits are comfortably financed by inflows through the capital and financial...

This papers estimates the equilibrium exchange rate for Armenia using three different approaches: the purchasing power parity (PPP) approach, the behavioral equilibrium exchange rate (BEER) approach, and the external sustainability (ES) approach. All three approaches suggest that the dram was...