Exchange rate mean reversion from real shocks within an intertemporal equilibrium model

The post Bretton Woods era has been characterized by real exchange rates that exhibit mean reversion, with mixed evidence as to whether this reversion is partial (PPP never holds) or essentially complete. This paper generates these stylized facts theoretically by synthesizing a simple intertemporal open economy model with the elasticities approach to the current account. A central feature of the model is the existence of non-traded goods. The model can generate partial or approximately complete mean reversion for the real exchange rate (depending on parameter values) if innovations in output are made up of permanent and temporary components. In addition, temporary output shocks generate a type of hysteresis wherein the short-run path for the exchange rate permanently alters its long-run equilibrium value.