The decline of the RMB against the US dollar means that the RMB has depreciated against the US dollar, and the same amount of RMB can only be exchanged for less US dollars than earlier.

Exchange rate is the exchange rate between two currencies, which can be regarded as the value of one country's currency against another. Exchange rate is also a financial means for a country to achieve its political goals.

The exchange rate will change because of interest rates, inflation, national politics and national economies. Exchange rate system can be divided into fixed exchange rate system and floating exchange rate system.

Extended data is divided according to the method of setting exchange rate, including base exchange rate and arbitrage exchange rate.

① Basic exchange rate. When setting exchange rates, countries must choose a currency as the main comparison object, which is called the key currency. According to the comparison of the actual value of domestic currency and key currency, the exchange rate between domestic currency and key currency is calculated, which is the basic exchange rate. Generally speaking, the US dollar is the currency used more in international payment. All countries regard the US dollar as the main currency for setting exchange rates, and often regard the exchange rate against the US dollar as the basic exchange rate.

2 exchange rate arbitrage. It refers to the exchange rate calculated by countries according to the basic exchange rate against the US dollar, which directly reflects the value ratio between other currencies.

Baidu encyclopedia-exchange rate