A floating exchange rate or fluctuating exchange or flexible exchange rate is a type of exchange-rate regime in which a currency's value is allowed to fluctuate in response to foreign-exchange market mechanisms. A currency that uses a floating exchange rate is known as a floating currency. A floating currency is contrasted with a fixed currency whose value is tied to that of another currency, material goods or to a currency basket.
In the modern world, most of the world's currencies are floating; such currencies include the most widely traded currencies: the United States dollar, the Indian rupee, the euro, the Norwegian krone, the Japanese yen, the British pound, and the Australian dollar. However, central banks often participate in the markets to attempt to influence the value of floating exchange rates. The Canadian dollar most closely resembles a pure floating currency, because the Canadian central bank has not interfered with its price since it officially stopped doing so in 1998. The US dollar runs a close second, with very little change in its foreign reserves; in contrast, Japan and the UK intervene to a greater extent, whereas India has seen medium range intervention by its central bank, the Reserve Bank of India.
From 1946 to the early 1970s, the Bretton Woods system made fixed currencies the norm; however, in 1971, the US decided no longer to uphold the dollar exchange at 1/35th of an ounce of gold, so that the currency was no longer fixed. After the 1973 Smithsonian Agreement, most of the world's currencies followed suit. However, some countries, such as most of the Gulf States, fixed their currency to the value of another currency, which has been more recently associated with slower rates of growth. When a currency floats, targets other than the exchange rate itself are used to administer monetary policy (see open-market operations).