The international benchmark price (middle price) is a middle price determined by banks for their foreign exchange business according to the foreign exchange market price. TTS and TTB prices are based on the benchmark price plus or minus the price difference. The benchmark price changes with the change of the foreign exchange market price, but when the foreign exchange market price changes little, the benchmark price can remain unchanged. For example, the price range between the United States and Japan in the foreign exchange market is116538+0.56438.500000065, but it ranges from 1 1.5 1/kloc-0. In China, the benchmark price is set by the People's Bank of China, and other banks set their own TTS and TTB prices according to the benchmark price of the People's Bank of China (China is the buying price, foreign exchange buying price and selling price). In the past, the Bank of China quoted only one foreign exchange rate a day, but now it may quote several benchmark prices according to the market at different times of the day. In your supplementary question, the Bank of China has set the benchmark price, but the spread of each bank is different, so our bill buying price, foreign exchange buying price, selling price and even different banks at the same time are different. At present, even the same domestic bank (for example, Bank of China) has different spreads among banks in different places, so our prices are different.