Bond X and Bond Y both have a face value of $1000 and both bonds have the same yield to maturity. Bond X has a coupon of 5% and will mature in 15 years. Bond Y has a coupon of 4% and will mature in 14 years. Which bond has the longer duration, and why? Or, explain why this question cannot be answered without doing the exact calculation. (Note: You do not have to calculate the exact duration, but make sure that your answer addresses all important variables).