Investment levels seem strongly correlated with natural resources (no surprise there), but don’t appear to have much relation to the ease of doing business in a country. Nigeria, Sudan, Angola, and the Republic of Congo are all major oil exporters, even though of the 46 African countries the World Bank included in its 2011 Doing Business rankings*, they were respectively rated #17, 25, 31 and 40. Chad, at #46, had more investment than Botswana at #3. And Somalia, a failed state that didn’t even make it into the Doing Business rankings, had only a touch less investment than vaunted reformer Rwanda. Fascinating stuff.
*Only the current year’s data are up on the Doing Business site, and some countries have shifted rankings between 2009 (for which we have investment data) and 2011 (the business rankings). For instance, I know that the DRC went from 183 of 183 in the world in Doing Business 2009 to a less whopping 175 of 183 in 2011. That said, with the exception of unusually rapid reformers such as Rwanda, I doubt the investment climate has changed that significantly (with the exception of political unrest) in most countries over the last two years.