Corruption Perceptions Index 2011: What’s in a number?

Deborah Hardoon, Transparency International’s Senior Research Coordinator, explains how the Corruption Perceptions Index measures corruption and how this can be an incentive for tackling it.

Since 1995, the Corruption Perceptions Index has scored and ranked countries from all around the world according to perceptions of the extent of corruption in the public sector. The simplicity of giving each country a single score has enabled the index to be a powerful awareness raising tool with global reach. The index provides a valuable insight in terms of how the extent of corruption can vary around the world. It also generates data which can be mapped and modeled to enhance our understanding of the relationship between corruption and other important outcomes. And as a single number cannot describe the full complexities and dynamics of corruption and its actors, it also paves the way for further and deeper analysis.

A measure of perceptions: As an individual, you might know of an incidence of a bribe being paid to a policeman for example, and exactly how much that bribe cost.

Or you may have read in the papers news of corruption in a particular government procurement contract. But cases of corruption, that we know or have evidence of, make up just a fraction of the full extent of corruption across society.

Corruption is by its very nature deliberately hidden, and being able to obtain information about particular cases depends on freedom of information, the quality of anti-corruption legislation and the effectiveness of the laws and institutions in terms of holding guilty parties to account.

Given the fundamental challenges of gathering evidence based data on corruption, the Corruption Perception’s Index takes a different approach. This index brings together a number of different data sources (in 2011 we use 17 separate surveys and assessments), which capture perceptions of the extent of corruption in the public sector of a country/territory. With this approach, in 2011 we are able to score and rank 183 countries/territories from around the world on the same scale.

Perceptions data has been shown to correlate very well with other indicators that use a more evidence based approach. For example, Transparency International’s Global Corruption Barometer 2010 asked people from 86 countries whether they had paid a bribe for public services.

When these results were plotted against the index scores for each country, we can clearly see that ordinary people are more likely to have to pay a bribe to access basic public services where corruption is perceived to be more prevalent.

People’s experiences of bribery in the 2010 Barometer compared to experts’ perceptions of corruption in the 2010 Corruption Perceptions Index.

What the data can tell us: The CPI 2011 allows us to compare 183 of these countries against each other. We can highlight at the global and regional level where countries and territories have been successful in controlling corruption. Looking at South America, Chile and Uruguay clearly stand out as having public sectors that are perceived as less corrupt than their neighbouring countries.

In Africa, we can point to Botswana, which is ranked as the cleanest country on the continent. Highlighting these differences and drawing attention to good country examples can be a powerful incentive for other countries to actively fight corruption and improve their relative position.

In contrast, at the bottom of the index, we find Somalia, a country ravaged by war and famine, and North Korea, a country with one of the worst human rights records in the world. Governments, businesses, and civil society in countries towards the bottom of the index should do all they can to fight corruption and pull them up and away from the bottom of the Corruption Perceptions Index.

At a macro level, the index can also be used to illustrate the relationship between the extent of corruption and other important outcomes. We can plot the Corruption Perceptions Index against the UN’s Human Development Index, and find that where there is perceived to be more corruption, human development outcomes tend to be lower.

Transparency International’s Bribe Payers Index (BPI) captures perceptions of the likelihood of companies to pay bribes when doing business overseas and the 2011 edition finds that in countries where the Corruption Perceptions Index scores are low (highly corrupt) companies from these countries are seen as more likely to pay bribes when doing business overseas.

Quantitative data is a great tool. We can paint maps and plot graphs of relationships, but it is also important not to stop at the score in the Corruption Perceptions Index when assessing corruption, but rather see it as a starting point for a more detailed exploration for a given country, sector or institution.

Understanding how corruption manifests itself in its many forms and as perpetrated by various actors, both those on the demand and the supply side require a much more detailed analysis and a host of diagnosis and assessment tools.

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Deborah Hardoon

About Deborah Hardoon

Deborah Hardoon is Senior Researcher at Oxfam.


12 Responses to Corruption Perceptions Index 2011: What’s in a number?

  1. Dave Shuttleworth 1 December 2011 at 10:13 am #

    Makes for interesting reading. I recently heard a statistic about South Africa’s corruption problems that implied that about 20% of the government’s public procurement budget ended up being wasted due to corruption (see link below). This obviously has a major impact on both the efficiency of public expenditure and the effectiveness of service delivery, but it surely could also be linked to other negative consequences such as inflation, which directly impacts the value of living wages.

  2. Helmut Reisen 1 December 2011 at 2:15 pm #


    as a researcher who uses the CPI numbers occasionally I am interested more in time series than in cross country comparisons. For example, I find it interesting to relate EITI membership or Chinese engagegement to subsequent CPI development.

    Can I find this somewhere on your site.? Have you done work on similar lines?

    Thanks for your attention,

  3. Deborah Hardoon
    Deborah Hardoon 1 December 2011 at 6:05 pm #

    Helmut – you are right that the CPI is a cross country index, and is not appropriate for time series analysis.

    We are always looking for ways to improve and increase the breadth of our corruption measurement and diagnosis toolkit. Please take a look at the GATEway site for more information on the tools we have developed from accross the movement and beyond, that capture different aspects of corruption, using different research methods and for different applications.

    The worldbank’s governance indicators are also designed to be used as time series data and may also be a useful resource for you research.

  4. aldiouma sow( legal adivor ALAC- SENEGAL 2 December 2011 at 1:43 pm #

    good ideas et good tool to fight corruption around the world

    we all support T.I for a world without corruption

  5. Jack one of the few remaining terrestrials who love Earth 2 April 2012 at 12:12 am #

    Are not your stats on perceived “democracy” anything more than simple greed based and greed driven mafia style exploitation? Sure everyone wants to better themselves, but wouldn’t truthful reporting rather that the genocide driven 2.5 planets of resources model….your impossible dream, be a more realistic approach? After all transparency based on propaganda is what this world needs less of! Esp your over-privileged smug models. Or to make the transparent even more obvious, if you invert your model and remove US manufactured wars, you find sustainability at the forefront . Don’t kill all the poor just because they disagree with multinational resource pigs like yourselves. Learn to live sustainably on our one planet and recognise those who, like yourselves, lie when all they have ever lived with are lies, If you are fooled or just plain stupid, these words are meant to educate. If you do this for profit, your children will die from your ignorance. Be wise and think in a sustainable context, not in a ‘Who is too scared to stand up to and/or is paid off by the truly corrupt’. Your facts are seriously compromised by the fear and the greed of people not paying attention to tomorrow. Please in the name of life on this planet, stop lying!

  6. Jack one of the few remaining terrestrials who love Earth 2 April 2012 at 12:36 am #

    Currently on Earth, 70% of global arms sales are US-based (NPR Radio broadcast 2009)
    Sustainability, as espoused by ALL our grandparents and great grandparents, is in fact the key to what may someday become a word resembling ‘democracy’, When tuberculosis kills so many of us while the rich compose statistics on how genocide driven greed is ‘good’ , we don’t stand a chance! Please be honest based upon the facts and transparency and not a mouthpiece for the war mongers!

  7. référencer son site 30 October 2012 at 6:45 am #

    Ou peut-on trouver la source exacte de cet article svp ? je l’ajoute à mes favoris. A bientôt.

    référencement gratuit référencer son site


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