Detecting excessive credit growth : an approach based on structural counterfactuals

The Basel credit-to-GDP gap is the single most popular measure of excessive credit growth and the financial cycle in general. It is based, however, on a purely statistical understanding of excessiveness: Growth is excessive if the credit-to-GDP ratio (i.e. the ratio of credit to nominal GDP) is significantly above its long-term trend. This paper presents an alternative approach where variation in the credit-to-GDP ratio is decomposed into its structural economic drivers. Some of these economic drivers are assumed to be non-excessive (aggregate demand and supply shocks), and others to be potentially excessive (all other shocks). Based on this identification, I construct a more structural credit gap measure that quantifies the impact of excessive drivers. In an early-warning exercise, I show that this gap measure performs particulary well in predicting financial crises at relatively short horizons.