登录之后可查看解析

Bond A has a yield advantage of 132 basis points relative to Bond B. An increase in Bond B’s credit rating will increase its price and lower its yield. Since we are looking at this in terms of Bond B: (1.32/-7.30) x 100 = -18.08219bp, the breakeven change in yield is –18.08219bp, or a decline in the yield on Bond B resulting in the widening of the spread between A and B by this amount. The increase in price for Bond B will result in capital gains for Bond B, which will offset A’s original yield advantage. Note that the CFA curriculum specifies using the bond with the greater duration which in this case would be bond A although as we have demonstrated in this question the bond with the shorter duration can also be used. Thus, if you are not told which bond to use to perform the calculation you should use the one with the greater duration.