The Fed model

To help keep inflation manageable, the Fed watches inflation indicators such as the Consumer Price Index (CPI) and the Producer Price Index (PPI). When these indicators start to rise more than 2-3% a year, the Fed will raise the federal funds rate to keep the rising prices under control. Because higher interest rates mean higher borrowing costs, people will eventually start spending less. The demand for goods and services will then drop, which will cause inflation to fall.

A good example of this occurred from 2001 to 2002, when the Fed cut the federal funds rate to 1.25%. This greatly contributed to the economy's 2003 recovery. By raising and lowering the federal funds rate, the Fed can prevent runaway inflation and lessen the severity of recessions.  When interest rates are rising, both businesses and consumers will cut back on spending. This will cause earnings to fall and stock prices to drop. On the other hand, when interest rates have fallen significantly, consumers and businesses will increase spending, causing stock prices to rise.

Interest rates also affect bond prices. There is an inverse relationship between bond prices and interest rates, meaning that as interest rates rise, bond prices fall, and as interest rates fall, bond prices rise. The longer the maturity of the bond, the more it will fluctuate in relation to interest rates. One way that governments and businesses raise money is through the sale of bonds. As interest rates move up, the cost of borrowing becomes more expensive. This means that demand for lower-yield bonds will drop, causing their price to drop. As interest rates fall, it becomes easier to borrow money and many companies will issue new bonds to finance expansion. This will cause the demand for higher-yielding bonds to increase, forcing bond prices higher. Issuers of callable bonds may choose to refinance by calling their existing bonds so they can lock in a lower interest rate.

The Fed uses its tools to control the supply of money to help stabilize the economy. When the economy is slumping, the Fed increases the supply of money to spur growth. Conversely, when inflation is threatening, the Fed reduces the risk by shrinking the supply.

To implement its primary task of controlling money supply, there are three main tools the Fed uses to change bank reserves:

    1.    A change in reserve ratio is seldom used but is potentially very powerful. The reserve ratio is the percentage of reserves a bank is required to hold against deposits.A decrease in the ratio will allow the bank to lend more, thereby increasing the supply of money. An increase in the ratio will have the opposite effect.

    2.    The discount rate is the interest rate that the central bank charges commercial banks that need to borrow additional reserves. It is an administered interest rate set by the Fed, not a market rate; therefore, much of its importance stems from the signal the Fed is sending to the financial markets (if it's low, the Fed wants to encourage spending and vice versa). As a result, short-term market interest rates tend to follow its movement. If the Fed wants to give banks more reserves, it can reduce the interest rate that it charges, thereby tempting banks to borrow more. Alternatively, it can soak up reserves by raising its rate and persuading the banks to reduce borrowing.

    3.    Open-market operations
Open-market operations consist of the buying and selling of government securities by the Fed. If the Fed buys back issued securities (such as Treasury bills) from large banks and securities dealers, it increases the money supply in the hands of the public. Conversely, the money supply decreases when the Fed sells a security. Note that the terms "purchase" and "sell" refer to actions of the Fed, not the public. For example, an open-market purchase means the Fed is buying but the public is selling. Actually, the Fed carries out open-market operations only with the nation's largest securities dealers and banks, and not with the general public. In the case of an open-market purchase of securities by the Fed, it is more realistic for the seller of the securities to receive a check drawn on the Fed itself. When the seller deposits it in his or her bank, the bank is automatically granted an increased reserve balance with the Fed. Thus, the new reserves can be used to support additional loans. Through this process, the money supply increases.

The monetary expansion following an open-market operation involves adjustments by banks and the public. (To find out more, see Formulating Monetary Policy.) The bank in which the original check from the Fed is deposited now has a reserve ratio that may be too high. In other words, its reserves and deposits have gone up by the same amount; therefore, its ratio of reserves to deposits has risen. To reduce this ratio of reserves to deposits, it chooses to expand loans.

When the bank makes an additional loan, the person receiving the loan gets a bank deposit. At this stage, when the bank makes a loan, the money supply rises by more than the amount of the open-market operation. This multiple expansion of the money supply is called the money multiplier. Bank loans and purchases of securities are described as bank credit. It is the existence of bank credit that makes the money stock larger than the monetary base, also known as "high-powered money". High-powered money consists of currency and bank deposits at the Fed.