The 2013 Commitment to Development Index (CDI) is out. The ranking, from the Center for Global Development, aims to say which rich countries have the overall best policies on development and which the worst. Unlike other indices, it doesn’t just look at overseas development assistance (“aid”) but at six other aspects of policy including technology, environment, trade and — controversially — openness to migration and promotion of international security. The CDI also weights the value of aid depending on how likely its authors think it is that the aid will actually contribute to development (for example, most aid to Afghanistan is included at only 26 cents per dollar). The ranking includes all of the members of the Development Assistance Committee of the Organisation for Economic Co-operation and Development (OECD)

There are no big surprises about the top three: they’re all Scandinavian. The US, however, has fallen down the chart under the Obama presidency although it seems to have been penalised very heavily for its new restrictions on immigration. At the bottom are South Korea and Japan. In past years, there has been a bit of to and fro by blog from the Japanese arguing that the index is unfair to them.

It’s easy to disagree with the index (why, for example, does the UK’s habit of stealing doctors and nurses from developing countries give it points in the index’s openness to migration category? Why does Slovakia top the environment list simply because it has no fossil fuels to produce?). The Index does, though. do what it set out to: it creates debate. It is also a beautiful example of how to lay out complex figures in easy-to-understand charts