Exchange rate changes have a direct regulatory effect on a country's import and export trade. Under certain conditions, by devaluing the local currency, that is, letting the exchange rate rise, it will promote exports and restrict imports; On the other hand, the appreciation of the domestic currency, that is, the decline of the exchange rate, plays a role in restricting exports and increasing imports.

The amount of foreign currency in a fixed unit depends on the value of each foreign currency. Except that the exchange rate of RMB against Belgian franc and Italian lira is ten thousand (10000) units and against Japanese yen is one hundred thousand (100000) units, the exchange rates of other foreign currencies are all one hundred (10000) units.