课后题问题如下：
An investor is considering the portfolio impact of a new 12-year corporate bond position with a $75 million face value, a 3.25% coupon, current YTM of 2.85%, modified duration of 9.887, and a price of 104.0175 per 100 of face value.
NO.PZ202112010200002202
问题如下：
What is the approximate VaR for the bond position at a 99% confidence interval (equal to 2.33 standard deviations) for one month (with 21 trading days) if daily yield volatility is 1.50% and returns are normally distributed?
选项：
A.
$1,234,105
B.
$2,468,210
C.
$5,413,133
答案讲解如下：A is correct. The expected change in yield based on a 99% confidence interval for the bond and a 1.50 bps yield volatility over 21 trading days equals 16 bps = (1.50 bps × 2.33 standard deviations × √21). We can quantify the bond’s market value
change by multiplying the familiar (–ModDur × ∆Yield) expression by bond price
to get $1,234,105 = ($75 million × 1.040175 × (–9.887 × .0016)).
讲义中问题如下
我的问题是，
这两道题在计算change in YTM时，讲义中用乘以4%的YTM了，但是在课后题的计算中，并没有乘以bond的YTM 2.85%，而是直接计算了。请问是为什么？
