Does the Corruption Perception Index for 129 Countries Converge Over Time?

By far, the most popular type of corruption measurements used is Corruption Perception Index published annually since 1995 by Transparency International. We examine whether country differences of the Corruption Perception Index existing in 2003 has narrowed by 2015 and if so, how fast. We deploy the convergence methodology to answer these questions for 129 countries. Results of our analysis indicate that the Corruption Perception Index for 129 countries is conversing toward a catch-up process as well as a reduction of dispersion. However, significant variations are discovered in the speed and timing of the convergence processes for the subgroups of countries defined by income and regions.