Assume you have a portfolio comprising 4 zero-coupon bonds that have 2 years to maturity and 6 zero-coupon bond with a maturity of 25 years. Assuming semi-annual compounding and that all bonds have a face value of 100 and that the yield curve is flat at 7% pa, what is the modified duration of this portfolio? 13.043 7.036 None of the answers provided are correct O 7.168 18.919