The Pricing of Unexpected Credit Losses

46 Pages Posted: 20 Sep 2007

See all articles by Jeffery D. Amato

Jeffery D. Amato

Goldman Sachs International

Eli M. Remolona

Bank for International Settlements (BIS) - Monetary and Economic Department

Date Written: November 2005

Abstract

Why are spreads on corporate bonds so wide relative to expected losses from default? The spread on Baa-rated bonds, for example, has been about four times the expected loss. We suggest that the most commonly cited explanations - taxes, liquidity and systematic diffusive risk - are inadequate. We argue instead that idiosyncratic default risk, or the risk of unexpected losses due to single-name defaults in necessarily small credit portfolios, accounts for the major part of spreads. Because return distributions are highly skewed, diversification would require very large portfolios. Evidence from arbitrage CDOs suggests that such diversification is not readily achievable in practice, and idiosyncratic risk is therefore unavoidable. Taking a cue from CDO subordination structures, we propose value-at-risk at the Aaa-rated con.dence level as a summary measure of risk in feasible credit portfolios. We find evidence of a positive linear relationship between this risk measure and spreads on corporate bonds across rating classes.

Keywords: credit spread puzzle, jump-at-default risk, Sharpe ratio, collateralised debt obligation

JEL Classification: C13, C32, G12, G13, G14

Suggested Citation

Amato, Jeffery D. and Remolona, Eli M., The Pricing of Unexpected Credit Losses (November 2005). BIS Working Paper No. 190, Available at SSRN: https://ssrn.com/abstract=860427 or http://dx.doi.org/10.2139/ssrn.860427

Jeffery D. Amato (Contact Author)

Goldman Sachs International ( email )

United States

Eli M. Remolona

Bank for International Settlements (BIS) - Monetary and Economic Department ( email )

IFC 2 Bldg, 78/F
Central
Hong Kong
Hong Kong
+852 2982 7150 (Phone)
+852 2982 7123 (Fax)