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1. In foreign trade, if a country's import volume exceeds its export volume in a certain period of time (usually one year), it is called surplus, that is, trade deficit or trade deficit. The deficit of international trade, under the condition of gold standard currency, needs to export gold to export surplus countries to pay off debts, otherwise trade cannot be reached. Under the credit currency system, there are diametrically opposite economic interests according to the different currencies used. If the deficit country liquidates the surplus country with its own currency, it is a credit purchase. Buying goods on credit from surplus countries for a long time will lead to the bankruptcy of manufacturing enterprises in surplus countries and the financial crisis in their banking industry.
2. If the currency of the surplus country is used for liquidation, it is a compensation trade act to hedge the deficit of the surplus country, which will reduce the debt of the surplus country to its own country.
3. If the third-party credit currency is used for settlement, the impact on the surplus countries is the same as that in the local currency. The central point of using monetary policy in capitalist countries is to adjust the money supply. Increasing the money supply is called "relaxing the money supply" and reducing the money supply is called "tightening the money supply".
4. The application of monetary policy can be divided into tight monetary policy and expansionary monetary policy. Generally speaking, the tight monetary policy tightens the economy by reducing the money supply, while the expansionary monetary policy expands the economy by increasing the money supply.
5. Tightening monetary policy is a policy tool adopted by the central bank to achieve macroeconomic goals. This monetary policy is a policy of tightening money when the economy is overheated, the total demand is greater than the total supply, and the economy is experiencing inflation. The central bank will adopt a tight monetary policy aimed at raising interest rates by controlling the money supply, so as to reduce investment and compress demand. The decline of total demand will make the total supply and total demand tend to be balanced and reduce the inflation rate.