a 2% rise in prices, they would expect to earn a real interest rate of 3%. The expected real interest rate is not a single number, as different investors have different expectations of future inflation. Since the inflation rate over the course of a loan is not known initially, volatility in inflation represents a risk to both the lender and the borrower.

In the case of contracts stated in terms of the nominal interest rate, the real interest rate is known only at the end of the period