Recent efforts to endogenize technological change in climate policy models demonstrate the importance of accounting for the opportunity cost of climate R&D investments. Because the social returns to R&D investments are typically higher than the social returns to other types of investment, any...

Aging populations in advanced economies are placing ever-increasing demands on government spending in the form of old-age benefits. Economies that have promised substantially more benefits than they have made provision to finance are heading into a prolonged era of fiscal stress. Unresolved...

We construct quarterly series of the revenues, expenditures, and debt outstanding for Japan from 1980 to 2010, and analyze the sustainability of the fiscal policy. We pursue three approaches to examine the sustainability. First, we calculate the minimum tax rate that stabilizes the debt to GDP...

Using a recursive empirical model of the real interest rate, GDP growth, and the primary government deficit in the U.S., I solve for the ergodic distribution of the debt/GDP ratio. If such a distribution exists, the government is satisfying its intertemporal budget constraint. One key finding is...

The global economy has a chronic shortage of safe assets which lies behind many recent macroeconomic imbalances. This paper provides a simple model of the Safe Asset Mechanism (SAM), its recessionary safety traps, and its policy antidotes. Safety traps share many common features with...

Fiscal sustainability is one of the most pressing policy issues of our time. Yet it remains difficult to quantify. Official debt is plagued with a number of measurement difficulties since its measurement reflects the choice of words, not policies. And forming the fiscal gap-the imbalance in the...

The question of what is a sustainable public debt is paramount in the macroeconomic analysis of fiscal policy. This question is usually posed as asking whether the outstanding public debt and its projected path are consistent with those of the government's revenues and expenditures (i.e. whether...

This paper makes two contributions. First, we examine the macroeconomic implications of Puerto Rico's Fiscal Plan that was certified in March 2017 for fiscal years 2017-18 to 2026-27. Second, we perform a Debt Sustainability Analysis (DSA) that incorporates the expected macroeconomic dynamics...

Debt sustainability is fundamentally a probabilistic concept: Debt is rarely sustainable with probability one. We propose an index of external debt sustainability that reflects this uncertainty. Namely we construct the index as the probability that, at the current exchange rate, net external...

The intertemporal budget constraint of the government implies a relationship between a ratio of current liabilities to the primary deficit with future values of inflation, interest rates, GDP and narrow money growth and changes in the primary deficit. This relationship defines a natural measure...