October 8th, 2004, 5:43 am
Arvanitis and Gregory (2001, Credit: The Complete Guide to Pricing, Hedging and Risk Management) suggest a method to hedge the counterparty risk on an IRS by a CDS. In short this method consists of hedging the IRS' mark-to-market value by buying a CDS with a notional equal to this m-t-m. Obviously, the CDS notional needs to be rebalanced since the IRS' m-t-m is fluctuating as well. They furthermore state that "if the default curve widens, the P&L on the swap will be negative (since the risky PV will decrease), while the long CDS position will increase in PV. However, it is only by chance that these will cancel. The authors suggest to choose the CDS so as to delta hedge, i.e. the deltas of the IRS and CDS are equal (delta is defined here as change with respect to a 1 bp change in the default swap spread)". They suggest e.g. to change the maturity of the CDS in order to get the required matching delta.I don't understand this, because the IRS has a delta (basis point value) based on a higher notional, e.g. a 10Y IRS, €100m notional swap has a bpv of approx. € 81,000. Let's assume the m-t-m of this IRS is € 5m, so effectively one would start to hedge € 5m by a CDS, which has a bpv of approx. € 4,000. The IRS and CDS delta's are different, but how would you obtain equal delta's? Would you have to make an adjustment, e.g. (exposure/IRS notional)?Thanks in advance,Kim