For the CDI, quantity is merely a starting point in a review that also assesses aid quality. The index penalizes "tied" aid, which recipients are required to spend on products from the donor nation; this prevents them from shopping around and raises project costs by 15%–30%. The index also subtracts debt payments the rich countries receive from developing countries on aid loans. And it looks at where aid goes, favoring poor, uncorrupt nations. Aid to Israel, for example, is counted at 13¢ on the dollar, since Israel is hardly poor. Aid to Mozambique, on the other hand, with its combination of high poverty and relatively good governance, is counted at 80¢ on the dollar. Finally, donors are penalized for overloading recipient governments with too many small aid projects. When projects are many and recipient officials few, the obligation to host visits from donor officials and file quarterly reports becomes a serious burden.
The index rewards governments for letting taxpayers write off charitable contributions, since some of those contributions go to Oxfam, CARE, and other nonprofits working in developing countries. All CDI countries except Austria, Finland, and Sweden offer such incentives. Since the index is about government policy, it counts only private giving that is attributed to tax incentives. Private giving to developing countries is higher in the United States than in most countries, at 10 cents per person per day. But even adding that to the 15 cents a day in government aid leaves the United States well short of donors such as Sweden and Denmark, which give 72 and 99 cents a day in government aid alone.
The differences between countries in raw aid quantity are dramatic, and as a result they heavily influence the overall aid scores. The Netherlands and the Scandinavian countries take the top four slots on aid, while Japan and the United States end up near the bottom. But quality matters too. Denmark earns its big lead on aid by eschewing small projects. And the United States would score higher if it did not tie 70% of its aid and gave less to autocrats in Russia, Jordan, Pakistan, and other countries.