The question of how scaling up public investment could affect fiscal and debt sustainability is key for countries needing to fill infrastructure gaps and build resilience. This paper proposes a bottom-up approach to assess large public investments that are potentially self-financing and reflect their impact in macro-fiscal projections that underpin the IMF’s Debt Sustainability Analysis Framework. Using the case of energy sector investments in Caribbean countries, the paper shows how to avoid biases against good projects that pay off over long horizons and ensure that transformative investments are not sacrificed to myopic assessments of debt sustainability risks. The approach is applicable to any macro-critical investment for which user fees can cover financing costs and which has the potential to raise growth without crowding-out.

This paper analyzes the macroeconomics of scaling up public investment in Burkina Faso under alternative financing options, including through foreign aid and a combination of tax adjustment and borrowing. Our findings are twofold: (1) raising official development assistance in line with the Gleneagles agreement provides scope for financing public investment at low cost and would have positive, but somewhat moderate, effects on aggregate output—the growth dividends in the nontradables sector would be partially offset by the Dutch disease in the tradables sector; and (2) the massive investment scaling-up contemplated under Burkina Faso’s “accelerated growth” strategy, while boosting medium- and long-term growth, would lead to unsustainable debt dynamics under a plausible tax adjustment and realistic concessional financing. A more gradual approach to closing Burkina Faso’s infrastructure gap is therefore desirable because it would take into account the needed time for the country to address its capacity constraints and to further improve investment efficiency.

This paper presents the DIGNAR (Debt, Investment, Growth, and Natural Resources) model, which can be used to analyze the debt sustainability and macroeconomic effects of public investment plans in resource-abundant developing countries. DIGNAR is a dynamic, stochastic model of a small open economy. It has two types of households, including poor households with no access to financial markets, and features traded and nontraded sectors as well as a natural resource sector. Public capital enters production technologies, while public investment is subject to inefficiencies and absorptive capacity constraints. The government has access to different types of debt (concessional, domestic and external commercial) and a resource fund, which can be used to finance public investment plans. The resource fund can also serve as a buffer to absorb fiscal balances for given projections of resource revenues and public investment plans. When the fund is drawn down to its minimal value, a combination of external and domestic borrowing can be used to cover the fiscal gap in the short to medium run. Fiscal adjustments through tax rates and government non-capital expenditures—which may be constrained by ceilings and floors, respectively—are then triggered to maintain debt sustainability. The paper illustrates how the model can be particularly useful to assess debt sustainability in countries that borrow against future resource revenues to scale up public investment.

We develop a model to study the macroeconomic effects of public investment surges in low-income countries, making explicit: (i) the investment-growth linkages; (ii) public external and domestic debt accumulation; (iii) the fiscal policy reactions necessary to ensure debt-sustainability; and (iv) the macroeconomic adjustment required to ensure internal and external balance. Well-executed high-yielding public investment programs can substantially raise output and consumption and be self-financing in the long run. However, even if the long run looks good, transition problems can be formidable when concessional financing does not cover the full cost of the investment program. Covering the resulting gap with tax increases or spending cuts requires sharp macroeconomic adjustments, crowding out private investment and consumption and delaying the growth benefits of public investment. Covering the gap with domestic borrowing market is not helpful either: higher domestic rates increase the financing challenge and private investment and consumption are still crowded out. Supplementing with external commercial borrowing, on the other hand, can smooth these difficult adjustments, reconciling the scaling up with feasibility constraints on increases in tax rates. But the strategy may be also risky. With poor execution, sluggish fiscal policy reactions, or persistent negative exogenous shocks, this strategy can easily lead to unsustainable public debt dynamics. Front-loaded investment programs and weak structural conditions (such as low returns to public capital and poor execution of investments) make the fiscal adjustment more challenging and the risks greater.

The question of how scaling up public investment could affect fiscal and debt sustainability is key for countries needing to fill infrastructure gaps and build resilience. This paper proposes a bottom-up approach to assess large public investments that are potentially self-financing and reflect their impact in macro-fiscal projections that underpin the IMF’s Debt Sustainability Analysis Framework. Using the case of energy sector investments in Caribbean countries, the paper shows how to avoid biases against good projects that pay off over long horizons and ensure that transformative investments are not sacrificed to myopic assessments of debt sustainability risks. The approach is applicable to any macro-critical investment for which user fees can cover financing costs and which has the potential to raise growth without crowding-out.

Despite relatively fast economic growth over the past few years, Cape Verde’s public debt to GDP ratio has risenrapidly. Achieving an appropriate balance among public investment, growth, and debt sustainability has become a priority for the Cape Verdean authorities. The IMF-World Bank debt sustainability analysis (DSA) framework has helped the authorities monitor the risks of debt stress. However, the DSA has a number of limitations. This paper intends to complement the DSA by addressing aspects currently not covered by the DSA. The paper evaluates public investment scaling-up strategies in Cape Verde by customizing the Buffie and others (2012) model for Cape Verde and conducting various scenario and sensitivity analysis. The paper assesses Cape Verde’s public debt risks, taking into account the link between public investment and growth. The paper concludes that the size of scaling-up and aspects of the economic structure have significant impact on the outcome of the public investment. A very large surge in public investment may lead to a debt to GDP ratio that reaches dangerous levels based on the usual DSA criteria. A more moderate scaling-up of public investment may contribute better to stable and sustained growth over the medium and long run. In addition, it is critical that the authorities ensure the quality of public investment.

This paper analyzes the tradeoffs between savings, debt and public investment in the Republic of Congo, a developing country with looming oil exhaustibility concerns. Our results highlight the risks to fiscal and capital sustainability of oil exporting countries from large scaling-up in public investment and oil price volatility in view of a projected decline in the oil revenue to GDP ratio. However, structural reforms that improve the efficiency of public investment can allow for a relatively faster buildup of sustainable public capital and sustain higher non-oil growth without adversely affecting the debt ratio or savings. Moreover, we show that even if a government pursues prudent fiscal policy that preserves resource wealth and debt sustainability in the face of exhaustible and volatile resource revenues, low public investment quality in the form of a misallocation of resources can hinder attainment of sustainable public capital and positive non-oil growth.