1。 Adjusting the statutory deposit reserve ratio can quickly change the deposit expansion multiple and money multiplier of commercial banks, thus adjusting the money supply. But the effect of this tool is too violent to be used often.

2。 Adjust the rediscount rate: → the cost of borrowing funds by commercial banks → the amount of credit provided by commercial banks to the society → the total amount of money supply; Change the eligibility conditions for rediscount → change the flow of funds → restrain or support the sector economy.

However, this tool has poor initiative and limited adjustment function.

3。 Buying and selling securities through open market business: → directly increase or decrease the base currency → adjust the money supply to affect the price of securities → adjust social credit.

Open market business has the characteristics of strong initiative, high flexibility, moderate regulation effect, good notification effect and wide influence.

Conditional and effective play to the role of open market business.