A powerful new understanding of global currency trends, including the rise of the Chinese yuanAt first glance, the modern history of the global economic system seems to support the long-held view that the leading world power's currency-the British pound, the U.S. dollar, and perhaps someday the...

We assess the role of economic and security considerations in the currency composition of international reserves. We contrast the “Mercury hypothesis” that currency choice is governed by pecuniary factors familiar to the literature, such as economic size and credibility of major reserve...