The Corruption Perceptions Index (CPI) is an index which ranks countries "by their perceived levels of public sector corruption, as determined by expert assessments and opinion surveys." The CPI generally defines corruption as an "abuse of entrusted power for private gain". The index is published annually by the non-governmental organisation Transparency International since 1995.
The 2021 CPI, published in January 2022, currently ranks 180 countries "on a scale from 100 (very clean) to 0 (highly corrupt)" based on the situation between 1 May 2020 and 30 April 2021. Denmark, New Zealand, Finland, Singapore, and Sweden are perceived as the least corrupt nations in the world, ranking consistently high among international financial transparency, while the most apparently corrupt are Syria, Somalia (both scoring 13), and South Sudan (11).
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