To solve the problem, we need to calculate the price of Bond B under different yield to maturity (YTM) scenarios and then address the conceptual question about interest rate risk.
Bond B has a face value of $1,000, a 10% annual coupon, and matures in 30 years. However, since only one more interest payment is to be made at its maturity, we treat it as a zero-coupon bond for the remaining period. We need to calculate its price for YTMs of 5%, 7%, and 11%.
The price of a bond is calculated using the present value formula:
\[ \text{Price} = \frac{C}{(1 + r)^n} + \frac{F}{(1 + r)^n} \]
Where:
- \( C \) is the annual coupon payment ($100 for a 10% coupon on $1,000 face value).
- \( F \) is the face value of the bond ($1,000).
- \( r \) is the yield to maturity (YTM).
- \( n \) is the number of years to maturity.
Since only one more payment is to be made, we consider \( n = 1 \).
YTM = 5%:
\[ \text{Price} = \frac{100}{(1 + 0.05)^1} + \frac{1000}{(1 + 0.05)^1} = \frac{100}{1.05} + \frac{1000}{1.05} \]
\[ \text{Price} = 95.24 + 952.38 = 1047.62 \]
YTM = 7%:
\[ \text{Price} = \frac{100}{(1 + 0.07)^1} + \frac{1000}{(1 + 0.07)^1} = \frac{100}{1.07} + \frac{1000}{1.07} \]
\[ \text{Price} = 93.46 + 934.58 = 1028.04 \]
YTM = 11%:
\[ \text{Price} = \frac{100}{(1 + 0.11)^1} + \frac{1000}{(1 + 0.11)^1} = \frac{100}{1.11} + \frac{1000}{1.11} \]
\[ \text{Price} = 90.09 + 900.90 = 990.99 \]
The question asks why the longer-term bond's price varies more than the price of the shorter-term bond when interest rates change. Let's evaluate the given statements:
I. Long-term bonds have greater interest rate risk than do short-term bonds.
- This statement is correct. Longer-term bonds are more sensitive to interest rate changes because the present value of their cash flows is affected more significantly over a longer period.
II. The change in price due to a change in the interest rate is larger for bonds with greater maturity.
- This statement is also correct. The longer the maturity, the more the bond's price will fluctuate with changes in interest rates.
III. The change in price due to a change in the required rate of return decreases as a bond's maturity increases.
- This statement is incorrect. The change in price actually increases with longer maturities.
IV. Long-term bonds have smaller interest rate risk than do short-term bonds.
- This statement is incorrect. Long-term bonds have greater interest rate risk.
- The calculated prices for Bond B are approximately $1047.62, $1028.04, and $990.99 for YTMs of 5%, 7%, and 11%, respectively.
- The correct reasons for the greater price variability of long-term bonds are statements I and II.