How Credit Risk, Yield, and Cash Flows Affect Bond Duration
Summary
The document examines whether investment-grade bonds or junk bonds necessarily have greater duration. It distinguishes measures based on contractual cash flows from effective or risk-adjusted duration, which estimates interest-rate sensitivity using modeled price changes. Effective duration can account for embedded options and may reflect credit-related reductions in expected cash flows, though the document notes that there is no single industry standard for incorporating credit risk.
For bonds with the same maturity and coupon, a higher yield can reduce duration, so a junk bond may have lower duration than an investment-grade bond. That comparison is conditional: coupon, price, yield, maturity, and embedded options all matter, and a discount bond can have greater duration than a premium bond. The responses also point out that high-yield bonds often have higher coupons or shorter maturities, while default risk can make contractual maturity a poor guide to actual rate exposure. The discussion does not establish a universal ordering between credit grades.
Key ideas
- Bond duration depends on the definition used, including whether it measures contractual cash-flow timing or effective price sensitivity.
- For otherwise similar bonds, higher yield can lead to lower duration.
- Credit grade alone does not determine which bond has greater duration.
- Default risk can make contractual maturity overstate a distressed bond’s effective interest-rate exposure.
- Coupon, price, maturity, and embedded options can change comparisons between bonds.
Tags
Full text
# Investment Grade Bond vs Junk Bond, whose duration is larger? # Investment Grade Bond vs Junk Bond, whose duration is larger? Just wondering how to calculate duration when take credit risk into consideration. I think if duration is calculated as weighted average of cashflow time, and weights are calculated using present values of cashflows, then Invest Grade Bond would have larger duration than Junk Bond. Is that the truth??? ## Answer by horseless (score 5) https://quant.stackexchange.com/a/25857 There are different measures and interpretations of duration. One, as has been pointed out already, has a formula weighting coupons and final contractual cashflow. Other definitions of duration take a broader perspective and relate it to the interest rate sensitivity of the security and not to a particular formula. These go by names such as effective or risk adjusted duration. Embedded options, for example, can be modeled into an interest rate tree, and the average of a one basis point increase and decrease in those rates and their impact on the price show the impact, or duration, of interest rates. Effective duration models can also incorporate credit risk but there is not an industry standard for that. It is important to not let a formula using the contractual final cash flow bias the results. For example, interest rate hedging may be done based on duration. A long term bond teetering on bankruptcy would have little or no effective duration, but using the contractual maturity might result in very inappropriate swap trades hedging risk that does not exist. ## Answer by Larasing (score 2) https://quant.stackexchange.com/a/25448 Duration is technically independent of credit risk. ANY bond's duration is just a matter of coupon, price, discount rate. However, many issued high yield bond ARE typically shorter, because of a. high coupon (all else equal makes duration shorter) b. they can't issue too long: they themselves don't want to finance expensively, and investors don't want to be stuck with crappy name for 10 years. Also given material default probability in high yield, there is a concept of "duration to worst" which is even shorter that's not in existence in investment grade market. ## Answer by doru (score 1) https://quant.stackexchange.com/a/25449 If you have a 0 coupon junk bond with the same time to maturity as a investment grade bond that pays coupons, the junk bond will have higher duration and visa versa. Calling it a junk or an ig bond doesn't change the duration, the formula is still the same so you can't say a ig bond always has a larger or smaller duration. ## Answer by dm63 (score 1) https://quant.stackexchange.com/a/25453 I agree with the assertion in the OP. If two bonds are identical then the interest rate sensitivity of the one with higher credit risk is lower. That's because the expected cash flows are smaller due to credit risk. ## Answer by rrg (score 1) https://quant.stackexchange.com/a/30289 Duration is a decreasing function of yield. It's simple to consider that lower yielding bonds (in IG or sovereign credit) will increase line item duration when compared against HY. ## Answer by Chris Andy (score 0) https://quant.stackexchange.com/a/25855 Ditto to Larasing. Any bond's duration is just a matter of coupon, price, discount rate. Credit risk does not factor into this equation. ## Answer by fatfingers (score 0) https://quant.stackexchange.com/a/45994 Credit risk factors into the discount rate and price. Consider an investment-grade bond and a junk bond that have the same maturity and coupon. Junk bond yield = benchmark + credit spread > Investment-grade yield Holding the coupon and time to maturity constant for both bonds, the junk bond with the higher yield and lower price to compensate for credit risk will have a lower duration. This doesn't hold if the junk bond is trading at a discount and the investment-grade bond is at par or a premium, which is more than possible. A bond at a discount has a duration ≥ duration of a premium bond. As time to maturity of both discount and premium bonds approach infinity, both durations converge as they approach the duration of a consol bond.
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