A bond’s duration can be interpreted in several ways. Macaulay duration is the weighted average time to receive all the bond’s cash flows and is expressed in years. A bond’s modified duration converts the Macaulay duration into an estimate of how much the bond’s price will rise or fall with a 1% change in the yield to maturity. Dollar duration measures the dollar change in a bond’s value to a change in the market interest rate, providing a straightforward dollar-amount computation given a 1% change in rates. Effective duration is a duration calculation for bonds that have embedded options.