Productivity, commodity prices and the real exchange rate: The long-run behavior of the Canada-US exchange rate

The paper examines the Canada-US real exchange rate since the early 1970s to test two popular explanations of the long-run real exchange rate based on the influence of sectoral productivities and commodity prices. The empirical analysis finds that both variables exert a significant long-run effect. However, the relation for the real exchange rate has shifted as the effect of each variable has become stronger and a positive trend is present since 1990. The effect of productivity, moreover, is opposite to that predicted by the standard Balassa-Samuelson theory. An explanation of these findings is suggested based on a general-equilibrium model that includes differentiated traded manufactures and homogeneous commodities.