In recent years there have been reports that a group of six Gulf countries (Bahrain, Kuwait, Oman, Qatar, Saudi Arabia, and United Arab Emirates) were considering the introduction of a single currency. Currently, these countries use currencies that are effectively pegged to the U.S. dollar. These countries rely heavily on oil exports to the rest of the world, and political leaders in these countries are concerned about diversifying trade. Based on this information, discuss the OCA criteria for this group of countries. What are the greatest potential benefits? What are the potential costs?