what is duration and how does that affect bond valuation 
bond valuation looks at discounted cash flows at their net present value if held to maturity duration instead measures a bond s price sensitivity to a 1 change in interest rates longer term bonds have a higher duration all else equal longer term bonds will also have a larger number of future cash flows to discount and so a change to the discount rate will have a greater impact on the npv of longer maturity bonds as well 