Mobilizing more revenue is a priority for sub-Saharan African (SSA) countries. Countries have to finance their development agendas, and weak revenue mobilization is the root cause of fiscal imbalances in several countries. This paper reviews the experience of low-income SSA countries in mobilizing revenue in recent decades, with two broad aims: identify empirical norms of how much and how fast countries have been able to mobilize more revenue and empirical determinants (panel estimates) of revenue mobilization. The paper finds that (i) the frequency distribution of changes in revenue ratios for SSA low-income countries (LICs) peaks at a pace of about 1⁄2-2 percentage points of GDP in the short-to-medium term and at a pace of about 2-31⁄2 percentage points of GDP over the longer term, and that (ii) almost all SSA-LICs managed to increase revenue ratios by more than 2 percentage points of GDP in the short-to-medium term, at least once in the last two decades. The sustainability of large increases in revenue ratios can be an issue, in particular for fragile countries. The panel estimates suggest that structural factors, such as per capita GDP, share of agriculture in GDP, inflation, degree of openness, and rents received from natural resources, are important determinants of tax revenue.

Mobilizing more revenue is a priority for sub-Saharan African (SSA) countries. Countries have to finance their development agendas, and weak revenue mobilization is the root cause of fiscal imbalances in several countries. This paper reviews the experience of low-income SSA countries in mobilizing revenue in recent decades, with two broad aims: identify empirical norms of how much and how fast countries have been able to mobilize more revenue and empirical determinants (panel estimates) of revenue mobilization. The paper finds that (i) the frequency distribution of changes in revenue ratios for SSA low-income countries (LICs) peaks at a pace of about ½-2 percentage points of GDP in the short-to-medium term and at a pace of about 2-3½ percentage points of GDP over the longer term, and that (ii) almost all SSA-LICs managed to increase revenue ratios by more than 2 percentage points of GDP in the short-to-medium term, at least once in the last two decades. The sustainability of large increases in revenue ratios can be an issue, in particular for fragile countries. The panel estimates suggest that structural factors, such as per capita GDP, share of agriculture in GDP, inflation, degree of openness, and rents received from natural resources, are important determinants of tax revenue.

An analysis of data for 39 sub-Saharan African countries during 1985–96 indicates that the variations in tax revenue-GDP ratios within this group are influenced by economic policies and the level of corruption. Namely, these ratios rise with declining inflation, implementation of structural reforms, rising human capital (a proxy for the provision of public services by the government), and declining corruption. The paper confirms that the tax revenue ratio rises with income, and that elements of a country’s tax base (such as the share of agriculture in GDP and the degree of openness) influence tax revenue.

The region is seeing a modest growth uptick, but this is not uniform and the medium-term outlook remains subdued. Growth is projected to rise to 3.4 percent in 2018, from 2.8 percent in 2017, on the back of improved global growth, higher commodity prices, and continued strong public spending. About 3⁄4 of the countries in the region are predicted to experience faster growth. Beyond 2018, growth is expected to plateau below 4 percent, modestly above population growth, reflecting continued sluggishness in the oil-exporting countries and sustained growth in non-resource-intensive countries. A number of countries (Burundi, DRC, South Sudan, and parts of the Sahel) remain locked in internal conflict resulting in record levels of refugees and Internally Displaced Persons, with adverse spillovers to neighboring countries.

This paper examines the output effects of changes in public expenditure and revenue in sub-Saharan African countries during 1990–2016. Fiscal multipliers in sub-Saharan Africa are somewhat smaller than those in advanced and emerging economies. The effect of changes in fiscal policy on output depends on the composition: cutting public investment has a larger effect on output than cutting public consumption or raising revenue. Episodes of fiscal consolidation have short- and medium-term output effects, but here, too, composition matters: fiscal consolidations based on reducing public investment have the largest effect on output, while fiscal consolidations based on revenue mobilization are less harmful than those based on public investment cuts. These findings suggest that the negative impact on growth can be mitigated through the design of fiscal adjustment and the accompanying policy environment.

Many sub-Saharan African countries face difficulty in raising tax revenue for public purposes. This study uses panel data on 43 sub-Saharan African countries during 1990-95 to measure the determinants of the tax share in GDP and to construct a measure of tax effort. The analysis suggests that the countries with a relatively high tax share tend to have a relatively high index of tax effort, although these results are not uniform across the countries. The results can be used to provide guidance on to the proper mix of fiscal policy in the event of budgetary imbalance.