Reserve Currency

The US dollar has been the dominant global reserve currency since the Bretton Woods agreement of 1944, when major economies formally pegged their currencies to the dollar, which was itself convertible to gold. Even after Bretton Woods collapsed in the early 1970s, the dollar retained its central role because of the size and depth of US financial markets, the reliability of US institutions, and the simple inertia of global trade being invoiced in dollars. Oil, for instance, is priced in dollars on global markets — a fact that reinforces demand worldwide. The US Dollar Index guide and crude oil guide both touch on this dynamic.

Being the reserve currency issuer carries privileges and burdens. The privilege — sometimes called "exorbitant privilege" — is the ability to borrow cheaply because there is structural global demand for your currency and bonds. The burden is that strong external demand for the dollar can keep it stronger than purely domestic economic conditions would warrant, pressuring export competitiveness. The euro, Chinese yuan, Japanese yen, and British pound also hold reserve status in smaller proportions, as tracked by the IMF's COFER (Currency Composition of Official Foreign Exchange Reserves) data.

A common confusion is assuming reserve-currency status is permanent. Historically, reserve currencies have shifted: the British pound dominated before World War II before ceding ground to the dollar. Economists debate whether the dollar's share is slowly declining as China's yuan internationalizes and alternatives emerge. FX reserves data from major central banks — available via the indicators section — offer one window into how that composition evolves over time.