Controlling the amount of money in the system is one of the most important functions of a government. Money is never simply personal. It is a matter of government policy. The more you understand how governments increase and decrease the amount of money available, the more you will be able to control your personal economy.

In the United States, the central bank is the Fed, or Federal Reserve. Every nation has an equivalent central bank. These banks monitor current economic conditions and respond if the central banks want to heat up or cool down the economy.

The news media use colorful language to say that the Fed is "pumping money" into the economy to calm fears of an economic panic. In other situations, the media refer to actions of the Fed intended to "drain money" from the system. Even though the media report that the Fed "pumps" money or "drains" money, they don't explain clearly how the Fed does this. How exactly does the Fed increase or decrease the amount of money?

First, it's important to be clear what it does NOT mean. The Fed does not pump more money into the system by printing more currency. Currency is not equivalent to money.

The Fed can control the money supply with several methods.

One method involves the reserve requirements for banks. A bank must keep a portion of its deposits on reserve. In other words, the bank can only loan out a percentage of its deposits as loans. The percentage it cannot loan out is the reserve.

Banks make money by loaning out customer deposits to other customer deposits. This means that if you deposit $1,000 in the bank, the bank loans most of your money to other customers. However, the bank is not allowed to loan out the full $1,000.

The Federal Reserve sets the reserve requirements for banks. Typically, the reserve ranges from 3-10% of its deposits. So, with your $1,000 deposit, the bank needs to keep on reserve only $30 with a 3% reserve and $100 with a 10% reserve. The bank is free to loan out whatever is left after the reserve requirement. With a 3% reserve the bank can loan out $970 of your money. With a 10% reserve, the bank can loan out only $900.

The Fed can use the reserve requirements to control the amount of money banks have available to loan. If the Fed wants to increase the amount of money in the economy, it reduces the reserve requirements. If it wants to decrease the amount of money, it increases reserve requirements. This is how the Fed "pumps" money into the system and "drains" money from the system.

With a lower reserve requirement, the bank has more money to loan. With a higher reserve requirement, the bank has less money to loan. This is the difference between loaning out 97% of its deposits with a 3% reserve rate and 90% of its deposits with a 10% reserve rate. The changes in reserve rates increase and decrease the money supply.

So even though the media talk about the Fed "pumping" more money into the economy, this language is a bit misleading. The banks do the "money-pumping" when the Fed allows banks to loan out a higher percentage of its deposits. This is one way the Fed controls the amount of money in the economic system.