This Time They're Different: Heterogeneity;and Nonlinearity in the Relationship;between Debt and Growth

We study the long-run relationship between public debt and growth in a large panel of countries. Our analysis takes particular note of theoretical arguments and data considerations in modelling the debt-growth relationship as heterogeneous across countries. We investigate the issue of nonlinearities ('debt thresholds') in both the cross-country and within-country dimensions, employing novel methods and diagnostics from the time-series literature adapted for use in the panel. We find some support for a nonlinear relationship between debt and long-run growth across countries, but no evidence for a common debt threshold within countries over time.