Independent solution

How to solve this Duration and Convexity question

Setup

Setup

Convert the supplied Macaulay duration to modified duration at the original yield.

Dmod=111.10=10D_{mod}=\frac{11}{1.10}=10

Model

Model

The first-order modified-duration approximation multiplies the yield change in decimal form by negative modified duration.

ΔPPDmodΔi\frac{\Delta P}{P}\approx-D_{mod}\Delta i

Compute

Compute

A 25-basis-point increase is 0.0025, producing a proportional price change of negative 0.025.

ΔPP10(0.0025)=0.025\frac{\Delta P}{P}\approx-10(0.0025)=-0.025

Answer

Answer

The approximate decline is 2.50%, corresponding to choice C.

2.50%(C)\boxed{-2.50\%\quad\text{(C)}}