“…With regard to so‐called “sudden stops,” we mention also the potentially harmful sovereign–bank link. We explain their potential effect on debt sustainability through the formula of the debt‐stabilizing primary balance: where pb is the primary balance/GNP (gross national product) ratio, i is the interest rate on the outstanding debt stock, g is the growth rate of the economy; T , E , D and Y are tax revenues, expenditures, debt and gross national product all in levels (Cafiso, ). From this point on, when we refer to sustainability, we mean stabilization as implied by equation ; the higher the primary balance needed to stabilize the debt‐to‐GNP ratio, the less sustainable public debt becomes…”