state-owned enterprises, with the remainder on-budget. The same study also finds that almost the entirety of infrastructure investment goes to just two sectors: energy (50 percent) and transport (45 percent).

Beyond these high-level estimations of expenditure and spending needs, little is known about infrastructure spending trends and patterns at the global level. This paper fills this gap by analyzing a new source of disaggregated infrastructure spending data covering some 75 countries over a period of 10 years, drawing from the World Bank’s novel BOOST database, complemented with data from relevant extra-budgetary channels. On this basis, the study aims to answer the following questions. What have been long term infrastructure spending trends across different types of countries? What are the patterns of infrastructure spending across sectors, functional categories, and institutional channels? Is there evidence of inefficiency, incoherence or cyclicality in infrastructure spending?

The rest of the paper proceeds as follows. The next section describes the data and methodology used to identify the infrastructure public spending trends, while the following one presents the results with a focus on roads and electricity spending. A fourth concluding section discusses the central findings and their policy implications.

# **2. Data and Methodology**

Public expenditure on infrastructure can be classified into three separate categories. The first category is on-budget expenditure, undertaken primarily by central government entities, such as ministries, which is reported in the budget itself and financed from domestic tax revenue mobilization. The second category is development expenditure provided by traditional and new foreign donors to governments and typically channeled outside of the public budget. The third category is off-budget expenditure, undertaken by corporatized or otherwise decentralized state entities, such as power utilities or Road Funds, which is not reported on the budget but can be found in the respective financial accounts.

The World Bank’s Public Expenditure Database BOOST compiles information on the level and composition of the first category of on-budget government expenditures for a growing number of emerging and low-income countries at quite a high level of granularity, currently around 75.<sup>3</sup> The sample is heterogeneous ranging from large countries (e.g. Argentina, Brazil, Indonesia, Mexico, and South Africa) to several small islands. It spans all major country income groups, including 22 low-income (LIC), 26 lower-middle income (LMIC), 21 upper-middle income (UMIC), and 8 high-income (HIC) countries, classified according to the level of gross national income per-capita. Due to the relatively small number of high-income countries, no disaggregated analysis is performed for this group. While the sample is not representative by design, with disproportionate representation of Sub-Saharan Africa and Latin America, it does account for about 40 percent of the population and 30 percent of the GDP of low- and middle-income countries globally (Appendix Table A2.2). Moreover, by excluding China and India, which are known to be relatively large spenders on infrastructure and often disproportionately influence global developing country averages, the sample provides a more realistic picture of the infrastructure spending situation across the bulk of emerging nations.

> 3 While there are 77 countries covered in BOOST, two had to be dropped. The first is Pakistan, where coverage is limited to the province of Punjab. The second is São Tomé Príncipe, where there were some concerns about data quality and coverage.

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