Business and default cycles for credit risk
利用1933-1997年美国数据，通过多变量不可观测成分框架分离信用周期与商业周期，发现GDP与商业失败率的周期协同主要发生在11-16年的长周期，而6年短周期中协同性不明确，并讨论了其对信用风险管理的启示。
Abstract Various economic theories are available to explain the existence of credit and default cycles. There remains empirical ambiguity, however, as to whether these cycles coincide. Recent papers suggest by their empirical research set‐up that they do, or at least that defaults and credit spreads tend to co‐move with macroeconomic variables. If true, this is important for credit risk management as well as for regulation and systemic risk management. In this paper, we use 1933–1997 US data on real GDP, credit spreads and business failure rates to shed new light on the empirical evidence. We use a multivariate unobserved components framework to disentangle credit and business cycles. We distinguish two types of cycles in the data, corresponding to periods of around 6 and 11–16 years, respectively. Cyclical co‐movements between GDP and business failures mainly arise at the longer frequency. At the higher frequency of 6 years, co‐cyclicality is less clear‐cut. We also show that spreads reveal a positive and negative co‐cyclicality with failure rates and GDP, respectively. This pattern disappears, however, if we concentrate on the post World War II period. We comment on the implications of our findings for credit risk management. Copyright © 2005 John Wiley & Sons, Ltd.