Some investment management firms also have more speculative specialist currency overlay operations, which manage clients' currency exposures with the aim of generating profits as well as limiting risk. Whilst the number of this type of specialist firms is quite small, many have a large value of assets under management (AUM), and hence can generate large trades.Hedge fundsHedge funds, such as George Soros's Quantum fund have gained a reputation for aggressive currency speculation since 1990. They control billions of dollars of equity and may borrow billions more, and thus may overwhelm intervention by central banks to support almost any currency, if the economic fundamentals are in the hedge funds' favor.Retail forex brokersRetail forex brokers or market makers handle a minute fraction of the total volume of the foreign exchange market. According to CNN, one retail broker estimates retail volume at $25–50 billion daily, which is about 2% of the whole market and it has been reported by the CFTC website that unexperienced investors may become targets of forex scams.Trading characteristicsMost traded currenciesCurrency distribution of reported FX market turnover Rank Currency ISO 4217code Symbol % daily share(April 2004)1 United States dollar USD $ 88.7%2 Eurozone euro EUR € 37.2%3 Japanese yen JPY ¥ 20.3%4 British pound sterling GBP £ 16.9%5 Swiss franc CHF Fr 6.1%6 Australian dollar AUD $ 5.5%7 Canadian dollar CAD $ 4.2%8 Swedish krona SEK kr 2.3%9 Hong Kong dollar HKD $ 1.9%10 Norwegian krone NOK kr 1.4%Other 15.5%Total 200%