Original practice · fully worked
Original variant: duration estimate of a yield shock
A seven-year corporate bond has Macaulay duration 7.2 years at an annual effective yield of 8%. Estimate the percentage price change, using modified duration, if the yield rises by 20 basis points.
- A
−1.56% - B
−1.44% - C
−1.33% - D
+1.33% - E
+1.56%
Answer and calculation
Modified duration is 7.2 divided by 1.08. Multiplying its negative by the 0.002 yield increase gives an estimated price change of negative 1.333%, choice C.
Setup
Setup
Convert the given Macaulay duration to modified duration at the current yield.
Dmod=1.087.2=6.666667 Model
Model
The first-order relative price change is negative modified duration times the yield change.
PΔP≈−DmodΔi Compute
Compute
Insert a positive 20-basis-point change.
PΔP≈−6.666667(0.002)=−0.013333 Answer
Answer
The estimated decline is 1.33%, choice C.
ΔP/P≈−1.33%(C)