BIS: The future of public debt

Conclusions from BIS working paper ( Bank for International Settlements ). The future of Public Debt: Prospects and Implications
“Our examination of the future of public debt leads us to several important conclusions.
First, fiscal problems confronting industrial economies are bigger than suggested by official debt figures that show the implications of the financial crisis and recession for fiscal balances. As frightening as it is to consider public debt increasing to more than 100% of GDP, an even greater danger arises from a rapidly ageing population. The related unfunded liabilities are large and growing, and should be a central part of today’s long-term fiscal planning. It is essential that governments not be lulled into complacency by the ease with which they have financed their deficits thus far. In the aftermath of the financial crisis, the path of future output is likely to be permanently below where we thought it would be just several years ago. As a result, government revenues will be lower and expenditures higher, making consolidation even more difficult. But, unless action is taken to place fiscal policy on a sustainable footing, these costs could easily rise sharply and suddenly.
Second, large public debts have significant financial and real consequences. The recent sharp rise in risk premia on long-term bonds issued by several industrial countries suggests that markets no longer consider sovereign debt low-risk. The limited evidence we have suggests default risk premia move up with debt levels and down with the revenue share of GDP as well as the availability of private saving. Countries with a relatively weak fiscal system and a high degree of dependence on foreign investors to finance their deficits generally face larger spreads on their debts. This market differentiation is a positive feature of the financial system, but it could force governments with weak fiscal systems to return to fiscal rectitude sooner than they might like or hope.
Third, we note the risk that persistently high levels of public debt will drive down capital accumulation, productivity growth and long-term potential growth. Although we do not provide direct evidence of this, a recent study suggests that there may be non-linear effects of public debt on growth, with adverse output effects tending to rise as the debt/GDP ratio approaches the 100% limit (Reinhart and Rogoff (2009b)).
Fourth, looming long-term fiscal imbalances pose significant risk to the prospects for future monetary stability”.

