How Big and Heterogeneous are the Effects of Currency Arrangements on Market Integration? A Price Based Approach

A rapidly expanding literature studies the effect of currency union and other exchange rate arrangements on goods market integration. All existing studies employ a methodology based on observed volumes of trade. However, from a theoretical point of view the connection between market integration and the volume of trade is loose. In this paper, we propose a different metric of market integration, based on the dispersion of prices of identical products in different countries. This metric is motivated by the theory of arbitrage in the presence of transaction costs. We apply the methodology to a unique 3-dimensional data set that includes prices of 95 very disaggregated goods (e.g., light bulbs and toothpaste with fluoride) in 83 cities around the world from 1990 to 2000. We find that a currency board or a currency union generally provides a stimulus to goods market integration that goes far beyond merely reducing exchange rate volatility to zero. However, there are important exceptions. Long-term currency unions exhibit greater integration than more recent currency boards. All existing arrangements can improve their integration further relative to a U.S. benchmark