Short answers, pulled from the story.
The Corruption Perceptions Index (CPI) is an annual ranking of countries by their perceived levels of public sector corruption, published by Transparency International, a German registered association, since 1995. It scores countries on a scale from 0 (highly corrupt) to 100 (very clean), based on assessments from experts and business executives.
In the 2025 CPI, published in February 2026, Denmark scored 89 and Finland scored 88, placing them among the top performers. South Sudan and Somalia each received a score of 9, and Venezuela scored 10, placing them among the lowest-ranked countries.
The CPI draws on 13 surveys and assessments from 12 institutions, including the World Bank, World Economic Forum, and Freedom House. Each country's data is standardized to a 0-100 scale using z-scores, then averaged; a country must be evaluated by at least three sources to receive a score. The methodology was revised in 2012 to allow consistent comparison across years.
Research published in 2007 and 2008 found that a one-unit increase in CPI score corresponded to a 1.7% increase in GDP growth. A 2019 study of 175 countries found that real per capita GDP decreased by around 17% in the long run when corruption worsened by one standard deviation on the reversed CPI.
Political scientist Dan Hough identified three flaws: the index reduces complex, varying forms of corruption to a single score; measuring perceptions may reinforce stereotypes rather than reflect reality; and the index excludes private-sector corruption entirely, meaning scandals like the Libor case and the Volkswagen emissions scandal are not counted. Johann Graf Lambsdorff, who created the original index, withdrew from work on it in 2009.
Yes. Transparency International has warned that a high domestic CPI score does not rule out involvement in transnational corruption. Sweden held the third-best CPI score in 2015 while its state-owned company TeliaSonera faced bribery allegations in Uzbekistan, and the Netherlands has a poor record of prosecuting companies that bribe foreign officials despite its high score.