Finance and Economics Discussion Series (FEDS)
June 2004
Understanding the Risk of Synthetic CDOs
Abstract:
Synthetic collateralized debt obligations, or synthetic CDOs, are popular vehicles for trading the credit risk of a portfolio of assets. Following a brief summary of the development of the synthetic CDO market, I draw on recent innovations in modeling to present a pricing model for CDO tranches that does not require Monte Carlo simulation. I use the model to analyze the risk characteristics of the tranches of synthetic CDOs. The analysis shows that although the more junior CDO tranches -- equity and mezzanine tranches -- typically contain a small fraction of the notional amount of the CDO's reference portfolio, they bear a majority of the credit risk. One implication is that credit risk disclosures relying on notional amounts are especially inadequate for firms that invest in CDOs. I show how the equity and mezzanine tranches can be viewed as leveraged exposures to the underlying credit risk of the CDO's reference portfolio. Even though mezzanine tranches are typically rated investment-grade, the leverage they possess implies their risk (and expected return) can be many times that of an investment-grade corporate bond. The paper goes on to show how CDO tranches and other innovative credit products, such as single-tranche CDOs and first-to-default basket swaps, are sensitive to the correlation of defaults among the credits in the reference portfolio. Differences of opinion among market participants as to the correct default correlation can create trading opportunities. Finally, the paper shows how the dependence of CDO tranches on default correlation can also be characterized and measured as an exposure to the business cycle, or as "business cycle risk." A mezzanine tranche, in particular, is highly sensitive to business cycle risk.
Keywords: Credit derivatives, credit risk, collateralized debt obligation
PDF: Full Paper
Disclaimer: The economic research that is linked from this page represents the views of the authors and does not indicate concurrence either by other members of the Board's staff or by the Board of Governors. The economic research and their conclusions are often preliminary and are circulated to stimulate discussion and critical comment. The Board values having a staff that conducts research on a wide range of economic topics and that explores a diverse array of perspectives on those topics. The resulting conversations in academia, the economic policy community, and the broader public are important to sharpening our collective thinking.