moderately unsatisfactory, this leads to further bunching in the middle of the distribution than would otherwise be the case.

Table 2 reports summary measures of project core characteristics in our two analytic samples. Two estimates of each measure are reported: the project-weighted and the dollar-weighted (by pledged loan volume) averages. The first information in the table depicts the distribution of the IEG project outcome scores. In the analytic data set there is a clear bunching of outcomes at the ‘satisfactory’ and ‘moderately satisfactory’ ratings while only 3% of projects are rated as highly satisfactory. Similarly, only 1% of projects were highly unsatisfactory and of the remaining 26% percent of projects deemed unsuccessful, 15% are ‘moderately unsatisfactory’. The fact that larger projects are slightly more likely to be rated successful is reflected in the fact that 76% of dollars was pledged to ultimately successful projects as opposed to 72% of projects.

We see that while World Bank investment projects are more numerous in Sub-Saharan Africa, when weighting by dollars they are greatest in the East Asia and Pacific region, followed by Latin America and the Caribbean. The Sustainable Development (SD) sector dominates by project count and by dollar volume but still almost half of projects are in the Equitable Growth, Finance, and Institutions (EFI) and Human Development (HD) sectors.<sup>10</sup> Slightly more than half of investment projects occur through the IDA instrument but 44% of projects fall within the less-concessional IBRD vehicle. In contrast, by dollar volume 64% of lending over the period studied was offered through IBRD.<sup>11</sup> The average real project size at time of approval stands at 89.6 million USD (measured in 2015 USD), while the slightly lower total amount committed, at 87.3 million USD, reflects the actual amount transferred including both partial cancellations and any increases in loans size that took place during project restructuring. The intended length at approval stands at five years, however project duration extension over the life of the project is quite common as the actual mean project length of the completed projects is 6.8 years.

We include two country-level measures, reported both at the beginning of projects and as the change over the project lifetime. The World Bank’s Country Policy and Institutional Assessment (CPIA) data provides a rating of countries’ policy and institutional frameworks and their conduciveness to poverty reduction, sustainable growth, and the effective use of development assistance. This rating is against a set of 16 criteria grouped in four clusters: economic management, structural policies, policies for social inclusion and equity, and public sector management and institutions. In terms of the country characteristics linked to these projects, the average CPIA stands at 3.5 and ranges from 1 (indicating weak country performance) to 6 (strong performance). The average change in score over the life of the projects is actually positive, indicating improvement in institutional environment over the implementation period. Average log

> 10 The sectors considered in this paper correspond to the World Bank’s three practice groups as of FY2018, in which the global practices (GPs) are nested. EFI includes the following: Finance and Markets; Governance; Macroeconomics and Fiscal Management; Poverty & Equity. HD includes Education; Health, Nutrition & Population; and Social Protection and Labor. Lastly, SD is comprised of: Agriculture and Rural Development; Energy and Extractives; Environment and Natural Resources; Social, Urban, Rural and Resilience; Transport and ICT; Water.

> 11 International Development Association (IDA) and International Bank for Reconstruction and Development (IBRD) are the two lending arms of the World Bank responsible for public sector projects. IDA and IBRD share the same staff and headquarters, and country eligibility to both funding sources is determined by their income level. National eligibility for the concessional IDA support is updated annually and for 2022 stands at a GNI per capita below US$1,205. Countries above this eligibility cut-off are generally eligible for IBRD financing.

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