Skip to content
All library documents

Interest-Rate Sensitivity and Credit Risk in CDS Positions

Article Quant Q&A · Author: beebeetatter

Summary

The document explains why a credit default swap can have interest-rate exposure even though its main market risk is credit. In a simplified reduced-form model with flat, deterministic interest and hazard rates, CDS value is framed as the difference between the discounted expected protection payment and the discounted premium stream. Their common credit-risky duration term drives rate sensitivity, while the credit hazard rate also directly affects the expected loss leg.

For a protection buyer, the sign of rate sensitivity depends on whether the contractual premium is above or below the market par spread: the premium liability or protection value dominates in different cases. At par, the model gives zero rate DV01; away from par, it gives rate exposure whose magnitude is described as much smaller than credit spread sensitivity. The answer also notes negative credit gamma for the protection buyer. These conclusions rely on a stripped-down model that omits accrued premium and other market details; the document does not calculate a concrete duration for the on-the-run CDX high-yield contract.

Key ideas

  • CDS rate exposure arises through discounting the credit-risky premium and protection cash flows.
  • A simplified model expresses value as the difference between expected loss payments and premium payments.
  • The sign of rate sensitivity depends on whether the contractual premium is above or below the market par spread.
  • At par, the simplified model implies zero rate DV01, while off-market contracts can have rate exposure.
  • The model describes rate sensitivity as smaller than credit spread sensitivity and identifies negative credit gamma for a protection buyer.

Tags

Full text
# Do CDS have interest rate exposure?


# Do CDS have interest rate exposure?












For hedging purposes, do CDS have interest rate exposure?

I've thought of CDS as a pretty direct proxy for credit risk, but on the other hand say if interest rates rise it would be harder for corporations to finance their debt and thus defaults would pickup.

To put it in concrete terms, what would you estimate the duration of the on-the-run CDX HY contract? Why?

## Answer by Mehness (score 5)

https://quant.stackexchange.com/a/40533

So as per my comments, the answer is yes. It's all about which leg is dominant, the loss payment, or the premium, if any. If you're short risk (bought protection) vs paying premium, then if the premium leg exceeds the loss leg (you're out of the money/OTM), then you want rates to rise to reduce the premium liability. If you're in the money (paying less than the protection's worth), then a drop in rates is good for you as your expected net loss leg 'asset' (vs the smaller premium leg liability) is less heavily discounted .

To see where this comes from let's just use the simplest possible CDS model. Flat, deterministic hazard rate and interest rate, in a reduced form model. It's amazing how much useful information (credit / rates deltas and gammas / cross-gammas etc) can be demonstrated in this simple setup, and it's totally shift f9 :). The MTM of the CDS (buyer's perspective), ignoring accrued and other diversions is given by$$PV_{CDS}=\lambda(1-R) \int_o^t\lambda e^{-(\lambda+r)t} \mathrm d t-p \cdot \int_o^t e^{-(\lambda+r)t} \mathrm d t$$

Where $p$ is the contract premium, $\lambda$ is the hazard rate, $R$ the recovery and $r$ the interest rate.The first term is the loss leg, the second the premium leg. This gives the MTM to be:$$PV_{CDS}=\left\{\lambda(1-R)-p \right\}\cdot \left \{{\frac{1- e^{-(\lambda+r)t}}{\lambda+r}} \right\} $$ The rightmost parentheses contain the credit risky duration of the CDS. The rates sensitivity is entirely driven by this term. Note that the market observed par spread, $s$, say, is simply given by $s=\lambda (1-R)$-if $p$ is struck at this market par spread, the MTM is zero.

I would suggest you try this formula to see what kind of sensitivities you observe for say 1b blips to $r$ and $\lambda$ (or equivalently spread $s=\lambda (1-R)$) with different market spreads vs the contractual premium $p$. You'll observe that the CDS has zero rates dv01 if on market ($p:=\lambda (1-R)$), +ve dv01 if OTM, and -ve if ITM. This is essentially as mentioned just because you have a derivative asset or liability in the different scenarios. Importantly, the rates dv01 is an order of magnitude smaller than the credit CR01, since the sensitivity to rates, as mentioned, is purely driven by the effect on the credit risky duration term, whereas the $\lambda$ sensitivity appears as a first order driver of the loss leg, which effect is much larger.

Lastly, you should see that the buyer of protection is short credit gamma - more of the risk is priced in, so marginal widenings are less important - and this effect is material and often lost on people new to trading the stuff!

Hope that helps, and would be happy to tie out on CDX HY if you'd like. Cheers.

Shown in full with attribution under the source's licence. Licence: CC BY-SA 4.0 (Stack Exchange)

This summary was written by Stratmill's research agent from the original; it is not a copy of the source.