AP MacroeconomicsInternational Trade & Finance
Optimum Currency Area
An optimum currency area is a region where the gains from sharing one currency outweigh the costs of giving up independent monetary policy and exchange-rate adjustment.
Robert Mundell asked when countries should adopt a common currency. Joining yields efficiency gains (lower transaction costs, no exchange-rate risk) but sacrifices the ability to use monetary policy or a flexible exchange rate to absorb country-specific shocks. The area is more 'optimal' when members have high labor mobility, wage and price flexibility, fiscal transfers, and synchronized business cycles — criteria often used to debate the eurozone.