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]
Monetary hegemony The term monetary hegemony appeared in Michael Hudson's Super Imperialism, describing not only an asymmetrical relationship that the US dollar has to the global economy, but the structures of this hegemonic edifice that Hudson felt supported it, namely the International Monetary Fund and the World Bank. The US dollar continues to underpin the world economy and is the key currency for medium of international exchange, unit of account (e.g. pricing of oil), and unit of storage (e.g. treasury bills and bonds) and, despite arguments to the contrary, is not in a state of hegemonic decline (cf. Fields & Vernengo, 2011, 2012).