The rate of exchange between future consumption (future dollars) and current consumption
(current dollars) is the pure rate of interest. Both people’s willingness to pay this difference for borrowed funds and their desire to receive a surplus on their savings give rise to an interest rate referred to as the pure time value of money. This interest rate is established in the capital market by a comparison of the supply of excess income available (savings) to be invested and the demand for excess consumption (borrowing) at a given time. If you can exchange $100 of certain income today for $104 of certain income one year from today, then the pure rate of exchange on a risk-free investment (that is, the time value of money) is said to be 4 percent (104/100 – 1).
The investor who gives up $100 today expects to consume $104 of goods and services in the future. This assumes that the general price level in the economy stays the same. This price stability has rarely been the case during the past several decades when inflation rates have varied from 1.1 percent in 1986 to 13.3 percent in 1979, with an average of about 5.4 percent a year from 1970 to 2001. If investors expect a change in prices, they will require a higher rate of return to compensate for it. For example, if an investor expects a rise in prices (that is, he or she expects inflation) at the rate of 2 percent during the period of investment, he or she will increase the required interest rate by 2 percent. In our example, the investor would require $106 in the future to defer the $100 of consumption during an inflationary period (a 6 percent nominal, risk-free interest rate will be required instead of 4 percent).
Further, if the future payment from the