Taxation, infrastructure investment, growth, and poverty reduction: A case study of Zimbabwe

In recent decades, Zimbabwe’s development record has been disappointing. In the last few years, a severe drought and the Covid-19 pandemic have added to the country’s development challenges. This paper is concerned with the long-run need to find a path toward faster growth in GDP, employment, and incomes, accompanied by more rapid progress on poverty reduction and other parts of the global sustainable development agenda. As part of this search, the country will need to address structural constraints including a large infrastructure gap, an inefficient government, and unhospitable business climate. Among these, this paper is focused on infrastructure and alternative means of financing scaled-up investments – what are the consequences of relying on domestic taxes compared to foreign financing? To address these questions, the paper draws on simulations with SDGSIM, a computable general equilibrium (CGE) model, designed for SDG analysis but applicable to analysis of policies in a wide range of areas, including growth, fiscal space, and external shocks. The model was adapted to the Zimbabwean context and calibrated to a database for 2016. The simulations cover the period 2016-2030 and analyzes the effects of alternative levels and priorities for government spending and resource mobilization (domestic and foreign). The simulation results cover a wide range of economic indicators, including some related to the global Sustainable Development Goal (SDG) agenda. The differences between the scenario results for GDP growth, household consumption, and poverty point to the importance of strong public investment management and, other things being equal, of targeting TFP gains to tradable sectors. The advantages of reliance on domestic taxation for the funding of expanded investment include slower debt accumulation and less reliance on the decisions of external actors. Tax reliance may also give the funders, the citizens, a stronger sense of ownership and right to monitor how the money is used, with a positive impact on investment productivity. On the other hand, before the investment have yielded sufficient returns, reliance on taxes reduces private purchasing power, leading to some combination of lower private consumption and investment. Raising the tax burden by 2-3 percent of GDP may also be administratively difficult. It would of course be possible to consider scenarios that split the funding burden between domestic taxes and foreign financing.