The Corruption Perceptions Index measures perceived levels of public sector corruption in 176 countries and territories around the world. It is compiled annually by Transparency International, a non-profit, non-governmental organization dedicated to fighting corruption.
The Index scores countries on a scale from 0 (highly corrupt) to 100 (very clean). While no country has a perfect score, two-thirds of countries score below 50, indicating a serious corruption problem. You can check the corruption index by topic or country. There are also other publications and articles on the site.