Assume you have a portfolio comprising 5 zero-coupon bonds that have 2 years to maturity and 6 zero-coupon bond with a maturity of 20 years. Assuming semi-annual compounding and that all bonds have a face value of 100 and that the yield curve is flat at 5% pa, what is the modified duration of this portfolio?

Group of answer choices

None of the answers provided are correct

7.752

13.711

10.732

7.609