They find that if debt growth falls by 1 percentage point and stays below baseline for a year, quarterly GDP growth is predicted to fall by 0.14 percentage point initially and by 0.22 percentage point over time.
The authors rightfully recognize, however, that the coefficient on debt growth may be biased upward because of reverse causality – that is, causality might run from higher economic growth to higher debt growth, because when desired purchases increase, households and business finance them by borrowing more.