when did the us dollar became the world currency
Reserve currency By the end of the 20th century, the United States dollar was considered the world's most dominant reserve currency.[1] The world's need for dollars has allowed the United States government as well as Americans to borrow at lower costs, granting them an advantage in excess of $100 billion per year.[2]
Spanish dollar Before the American Revolution, owing to British mercantilist policies, there was a chronic shortage of British currency in Britain's colonies. Trade was often conducted with Spanish dollars that had been obtained through illicit trade with the West Indies. Spanish coinage was legal tender in the United States until the Coinage Act of 1857 discontinued the practice. The pricing of equities on U.S. stock exchanges in ​1⁄8-dollar denominations persisted until the New York Stock Exchange converted first to pricing in sixteenths of a dollar on 24 June 1997, and shortly after that, to decimal pricing.