REUTERS/Bazuki Muhammad
We've laid out which countries are in the very upper end of the ranks. We also looked at where they were last year, and where they were five years ago, in the 2011 index.
The World Bank calculates its own score for each country, based on the "distance to frontier" (DTF). That tracks how far each country is from the best ever score for a number of different measures.
Those measures include things like how long it takes to get necessary permits, how long it takes to establish a business, and how burdensome the regulatory and tax environments are.
It's one of the most well-respected indexes on economic performance in the world, and there's fierce competition for a place in the upper ranks.
Here's how those best countries look this year.