The key thing is that the data is "Corruption Perceptions" not actual corruption. Here is a link with to their FAQs which explain more details. Also they menti

The key thing is that the data is "Corruption Perceptions" not actual corruption. Here is a link with to their FAQs which explain more details. Also they mention there is a detailed sources description document if you download the raw data. http://transparency.org/cpi2012/in_detail http://transparency.org/cpi2012/in_detail EDIT: D'oh, looks like jlmendezbonini beat me to the punch.