Effective duration indicates the sensitivity of a bond’s price to a 100-bps parallel shift of the benchmark yield curve in particular, the government par curve; assuming no change in the bond’s credit spread.
The flowing procedure is used to apply this formula in practice.
The following figure compares the effective duration of option-free, callable and putable bonds.
The effective durations of various types of instruments are shown in the table below.
Type of Bond | Effective Duration |
Cash | 0 |
Zero-coupon bond | ≈ Maturity |
Fixed-rate bond | < Maturity |
Callable bond | ≤ Duration of straight bond |
Putable bond | ≤ Duration of straight bond |
Floater (Libor flat) | ≈ Time (in years) to next reset |