6. 
Lisa Ying manages a fixed income portfolio of three bonds as shown in the following table. The duration of her portfolio is closest to:  
 
  
Bond  |  
Maturity  |  
Price  |  
Par Amount  |  
Duration  |   
A  |  
15-year  |  
$110.3412  |  
$10 million  |  
7.39  |   
B  |  
20-year  |  
$101.4835  |  
$5 million  |  
9.21  |   
C  |  
25-year  |  
$86.2746  |  
$8 million  |  
12.21  |  
  
 
  
A. 9.24  
B. 9.60  
C. 28.81  
 
 |  
 |  
 Ans: A;  
The market values of the bonds (Price×Par Amount) are respectively  
Bond A: 110.3412/100×10,000,000=$11,034,120  
Bond B: 101.4835/100×5,000,000=$5,074,175  
Bond C: 86.2746/100×8,000,000=$6,901,968  
They sum up to a total portfolio value of $23,010,263.  
Therefore, the duration of the portfolio =  
(11,034,120/23,010,263×7.39)+ (5,074,175/23,010,263×9.21)+ (6,901,968/23,010,263×12.21)  
=9.24  |