A picture of the underlying logic that penetrates the monetary system This super savings system diagram is actually a "microscope" for observing the transmission of central bank monetary policy. Help brothers understand the underlying logic of finance, from phenomena to mechanisms, and dissect where money comes from, where it goes, and how it is regulated, truly understanding the operational code of China's monetary system. Starting from the formula for excess reserve requirements, variables such as foreign exchange reserves and central bank debt issuance are linked to form a monetary cycle that includes the central bank, banks, enterprises, and residents How does the settlement and sale of foreign exchange reflect the entity's foreign-related behavior? How to regulate cross-border capital flows through foreign exchange reserve requirements? How can the adjustment of the foreign exchange settlement and sale system in history reshape market expectations? Essentially, the excess reserve system is the "trading interface" for the central bank to regulate the base currency. Through it, one can understand how monetary policy plays a game between internal and external balance - when foreign exchange reserves change, how does the central bank hedge liquidity through tools? How can overstocking become a barometer when market liquidity is abundant or tight? For the study of monetary finance, this chart is a key anchor point for understanding currency creation, cross-border capital flows, and the central bank's policy toolbox. It helps brothers to break down the underlying financial logic of "where money comes from, where it goes, and how it is regulated" from phenomenon to mechanism, and truly understand the operating password of China's monetary system.