What Do We Know About Loss Given Default?

Abstract

The New Basel Accord will allow internationally active banking organizations to calculate their credit risk capital requirements using an internal ratings based (IRB) approach, subject to supervisory review. One of the modeling components is loss given default (LGD), the credit loss incurred if an obligor of the bank defaults. The flexibility to determine LGD values tailored to a bank's portfolio will likely be a motivation for a bank to want to move from the foundation to the advanced IRB approach. The appropriate degree of flexibility depends, of course, on what a bank knows about LGD broadly and about differentiated LGDs in particular; consequently supervisors must be able to evaluate "what a bank knows." The key issues around LGD are: 1) What does LGD mean and what is its role in IRB? 2) How is LGD defined and measured? 3) What drives differences in LGD? 4) What approaches can be taken to model or estimate LGD? By surveying the academic and practitioner literature, with supportive examples and illustrations from public data sources, this paper is designed to provides basic answers to these questions. The factors which drive significant differences in LGD include place in the capital structure, presence and quality of collateral, industry and timing of the business cycle.

Keywords: New Basel Accord, credit risk

JEL Classification: G21, G28