The Dollar Duration is a measure of a bond's sensitivity to changes in the market interest rate. A bond with a high dollar duration will experience a large change in value when the interest rate changes, while a bond with a low dollar duration will have only a small change in value.Why is the dollar duration important?Because it can help investors to determine how much risk they are taking on when they invest in a bond. A bond with a high dollar duration is considered to be more risky than a bond with a low dollar duration.When interest rates rise, the value of a bond with a high dollar duration will fall more than the value of a bond with a low dollar duration. And when interest rates fall, the value of a bond with a high dollar duration will rise more than the value of a bond with a low dollar duration.So, if you are investing in a bond, it is important to know the bond's dollar duration. That way, you can be aware of the level of risk you are taking on.