Page 51 - PowerPoint Presentation
P. 51

LOS 36.j: Compare effective durations of                       READING 36: VALUATION AND ANALYSIS: BONDS WITH EMBEDDED OPTIONS
     callable, putable, and straight bonds.

     Both call and put options have the potential to reduce the life of a bond, so the             MODULE 36.5: DURATION
     duration of callable and putable bonds will be less than or equal to the duration of
     their straight counterparts.

     • Effective duration (callable) ≤ effective duration (straight).                Effective duration (straight bonds) is relatively
     • Effective duration (putable) ≤ effective duration (straight).                 unaffected by changes in interest rates; but:
     • Effective duration (zero-coupon) ≈ maturity of the bond.                      • an increase (decrease) in rates would decrease the
     • Effective duration of fixed-rate coupon bond < maturity of the bond.             effective duration of a putable (callable) bond.
     • Effective duration of floater ≈ time (in years) to next reset.

     LOS 36.k: Describe the use of one-sided durations and key rate durations to evaluate the interest rate sensitivity
     of bonds with embedded options.



                                                                                            But value of a callable bond is capped by its call
                                                     In a normal yield curve:               price: it will not increase beyond the call price
                                                     • value of call option falls (and rises   (irrespective of how low interest rates fall).
                                                        when yields drop)
                                                     • value of a put option increases      Similarly, the value of a putable bond is more
                                                        (and falls when yields increase)    sensitive to downward movements in yield curve than
                                                                                            upward movements.





     One-sided durations—only apply when interest rates rise (or, only when rates fall)—they are better at capturing interest rate
     sensitivity than simple effective duration:
     • Callable bonds: when at-the-money (or near-the-money):                 (the price change of a callable when rates fall is smaller
             • One-sided down-duration < one-sided up-duration                than the price change for an equal increase in rates).

     • Putable bond: when near-the-money:
            • larger one-sided down-duration > one-sided up-duration.
   46   47   48   49   50   51   52   53   54   55   56