At present, the fluctuation range of RMB-USD trading price in China inter-bank spot foreign exchange market is five thousandths, that is, the daily trading price of RMB-USD in the inter-bank spot foreign exchange market can fluctuate within five thousandths of the central parity of RMB-USD announced by China Foreign Exchange Trading Center on that day, while the euro, Japanese yen, Hong Kong dollar and British pound in the inter-bank foreign exchange market fluctuate by 3% above and below the central parity of non-US dollar currencies announced by China Foreign Exchange Trading Center. Banks should manage the maximum bid-ask spread of the listed exchange rate of USD against RMB. The interval between the highest selling price and the lowest buying price of USD (cash) on that day shall include the middle price of that day, and the difference between the highest selling price and the lowest buying price of cash shall not exceed 1% of the middle price of that day, and the difference between the highest selling price and the lowest buying price of cash shall not exceed 4% of the middle price of that day. Within the above range, banks can adjust the buying and selling prices of cash and cash by themselves.