The pound sterling, commonly known simply as the pound, is the official currency of the United Kingdom, Jersey, Guernsey, the Isle of Man, South Georgia and the South Sandwich Islands, the British Antarctic Territory and Saint Helena, Ascension and Tristan da Cunha. It is subdivided into 100 pence. A number of nations that do not use sterling also have currencies called the "pound". The British Crown dependencies of Guernsey and Jersey produce their own local issues of sterling: 'Guernsey pound' and 'Jersey pound'. The pound sterling is also used in the Isle of Man, Gibraltar, the Falkland Islands, and Saint Helena and Ascension Island in Saint Helena, Ascension and Tristan da Cunha. Manx, Gibraltar, Falkland Islands and Saint Helena pounds are separate currencies, pegged at parity to the pound sterling. Within the UK, some banks operating in Scotland and Northern Ireland produce private sterling denominated banknotes. Sterling is the fourth most traded currency in the foreign exchange market, after the United States dollar, the euro, and the Japanese yen. Together with those three currencies it forms the basket of currencies which calculate the value of IMF special drawing rights, with an 11.3% weighting as of 2011. Sterling is also the third most held reserve currency in global reserves.