The foreign exchange market is unique for several reasons, mainly because of its size. Trading volume in the forex market is generally very large. As an example, trading in foreign exchange markets averaged $5.1 trillion per day in April 2016, according to the Bank for International Settlements, which is owned by 60 central banks and is used to work in monetary and financial responsibility. The largest trading centers are London, New York, Singapore, and Tokyo. It can also involve trading currency on the foreign exchange market. For example, a trader is betting a central bank will ease or tighten monetary policy and that one currency will strengthen versus the other. When trading currencies, they are listed in pairs, such as USD/CAD, EUR/USD, or USD/JPY. These represent the U.S. dollar (USD) versus the Canadian dollar (CAD), the Euro (EUR) versus the USD and the USD versus the Japanese Yen (JPY).