This Exam FM sample reference tests Portfolio Weight for a Target Duration. Bond A has price 1055.50 and Macaulay duration 2.8381 years; the one-year zero has duration 1. Solving the market-value weighted duration equation gives 54.403% in Bond A, choice D.
These notes identify the calculation error associated with each wrong letter when that error is reproducible.
AChoice A uses face amounts rather than market-value weights in the portfolio duration.
BChoice B omits the year-3 coupon from Bond A's duration numerator.
CChoice C assumes the target duration is the simple midpoint of the two component durations.
EChoice E rounds Bond A's duration to 2.8 before solving the weight equation.
Original practice · fully worked
Original variant: duration of a stated two-bond allocation
A portfolio places 60% of market value in the three-year 6% coupon bond described by cash flows 60, 60, and 1,060, priced at a 4% yield. The remaining 40% is in a one-year zero. Determine the portfolio's Macaulay duration.
A 1.8381 years
B 2.0000 years
C 2.1029 years
D 2.3024 years
E 2.8381 years
Variant answer in brief
The coupon bond duration is 2.8381 years. Applying the stated 60%-40% market-value mix gives portfolio duration 2.1029 years, choice C.
Setup
Setup
Discount the coupon bond cash flows at 4% and calculate its duration.
DA=2.8381263
Model
Model
The one-year zero has Macaulay duration one.
DZ=1
Compute
Compute
Use the market-value allocation as the duration weights.
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