Transparency International released annual data for the Corruption Perceptions Index. The Economist plotted it against the UN's Human Development Index:
Comparing the corruption index with the UN's Human Development Index (a measure combining health, wealth and education), demonstrates an interesting connection. When the corruption index is between approximately 2.0 and 4.0 there appears to be little relationship with the human development index, but as it rises beyond 4.0 a stronger connection can be seen. Outliers include small but well-run poorer countries such as Bhutan and Cape Verde, while Greece and Italy stand out among the richer countries.
Interesting, although I suspect that the indices have some factors in common.