Internet Center for corruption research
HomeCorruption Perceptions Index2003Background information collage money students passau shaking hands
Contact information
Research Area
Corruption Perceptions Index
2009 and later
older indices
childhood days
Lecture and Workshops
What is the Corruption Perceptions Index?

The TI Corruption Perceptions Index (CPI) this year ranks 133 countries in terms of the degree to which corruption is perceived to exist among public officials and politicians. It is a composite index, drawing on 17 different polls and surveys from 13 independent institutions carried out among business people and country analysts, including surveys of residents, both local and expatriate. In 2002, the CPI included only 102 countries. The large increase in coverage relates to the fact that more valid and reputable sources have been found that can be incorporated.

For the purpose of the CPI, how is corruption defined?

The CPI focuses on corruption in the public sector and defines corruption as the abuse of public office for private gain. The surveys used in compiling the CPI tend to ask questions in line with the misuse of public power for private benefit, with a focus, for example, on bribe-taking by public officials in public procurement. The sources do not distinguish between administrative and political corruption.

Why is the Corruption Perceptions Index a valuable tool?

Because the CPI is derived from 17 different surveys that garner the perceptions of both residents and expatriates, both business people, academia and risk analysts, the index provides a snapshot of the views of decision-makers, who take key decisions on investment and trade. The CPI builds public awareness of the corruption issue, and it draws the attention of governments to the negative image of their nation that low rankings in the CPI reflect, adding another reason for them to address the problem.

What is the difference between the CPI and TI's Global Corruption Barometer (GCB)?

The CPI aims at assessing levels of corruption across countries, while the Global Corruption Barometer (see is concerned with attitudes that the general public forms vis--vis these levels of corruption. One question in the GCB asks respondents how significantly corruption affects their personal and family life. The resulting attitudes can vary considerably and do not necessarily correlate with levels of corruption. Respondents in some countries may be capable of living with high levels of corruption while for others even low levels of corruption provoke serious concerns.

What role is played by exporters in international criminal transactions?

On 14 May 2002, TI published the second Bribe Payers Index BPI), which ranked exporting countries according to the propensity of companies from those countries to offer bribes abroad. The BPI is accessible on the internet at The BPI complements the CPI and underlines the point that corruption in international business transactions involves both those who take and those who give. Looking only at those who take, the CPI provides an incomplete picture.

Is it right to conclude that the country with the lowest score is the world's most corrupt country?

No. The country with the lowest score is the one perceived to be the most corrupt of those included in the index. The CPI is based on polls that are snapshots in time and reflect both opinions and experience. Furthermore, there are almost 200 sovereign nations in the world, and the CPI 2003 ranks only 133.

Why is the CPI based only on perceptions?

It is difficult to base comparative statements on the levels of corruption in different countries on hard empirical data, e.g. by comparing the number of prosecutions or court cases. Such cross-country data does not reflect actual levels of corruption; rather it highlights the quality of prosecutors, courts and/or the media in exposing corruption. The only method of compiling comparative data is therefore to build on the experience and perceptions of those who are most directly confronted with the realities of corruption.

Was there any change in the target groups polled for the CPI this year?

The robustness of the CPI findings is enhanced by the fact that residents' viewpoints are found to correlate well with those of expatriates. In the past, expatriates surveyed were often western businesspeople. The viewpoint of less developed countries seemed underrepresented. This has changed. On behalf of Transparency International, Gallup International surveyed respondents from emerging market economies, asking them to assess the performance of public servants in industrial countries. A related approach was carried out by Information International. The results from these surveys correlate well with other sources, indicating that the CPI gathers perceptions that are invariant to cultural preconditions and represent a global perspective.

What are the criteria in determining which surveys are used?

TI seeks excellent data for the CPI and, to qualify, the data has to be well documented, and it has to be sufficient to permit a judgment on its reliability. TI strives to ensure that the sources used are of the highest quality, that the survey work is performed with complete integrity and that the methodologies used to analyse findings are first-class. A more detailed description of the underlying methodology has been written for the 2003 index and is available at or at The methodology used is reviewed by a Steering Committee consisting of leading international experts in the fields of corruption, econometrics and statistics. Members of the Steering Committee make suggestions for improving the CPI, but the management of TI takes the final decisions on the methodology used.

Which countries are included in the CPI 2003?

TI requires at least three sources to be available for a country before considering the database sufficiently robust for that country to be ranked in the CPI. The following countries were in the CPI 2003, but not the CPI 2002: Algeria, Armenia, Bahrain, Belize, Bosnia & Herzegovina, Congo (Republic of), Cuba, Cyprus, Gambia, Iran, Iraq, Kuwait, Kyrgyzstan, Lebanon, Libya, Macedonia, Mali, Mozambique, Myanmar, Oman, Palestine, Papua New Guinea, Qatar, Saudi Arabia, Serbia & Montenegro, Sierra Leone, Sudan, Syria, Tajikistan, United Arab Emirates and Yemen.

Countries with only two sets of data (and therefore not included) were: Afghanistan, Antigua and Barbuda, Bahamas, Barbados, Benin, Bermuda, Cayman Islands, Chad, Congo (Democratic Republic of), Dominica, Eritrea, Fiji, Gabon, Grenada, Guinea-Bissau, Liberia, Macau, Malta, Mongolia, Nepal, Niger, North Korea, Rwanda, Seychelles, Somalia and Turkmenistan.

Countries with only one set of data were: Andorra, Anguilla, Aruba, Bhutan, Brunei, Burkina Faso, Burundi, Cambodia, Cape Verde, Central African Republic, Comoros, Djibouti, East Timor, Equatorial Guinea, French Guiana, Guadeloupe, Guinea, Guyana, Laos, Lesotho, Liechtenstein, Maldives, Martinique, Mauritania, Neth. Antilles, Palau, Puerto Rico, Samoa, Sao Tome & Principe, St Kitts & Nevis, St Lucia, St Vincent & the Grenadines, Suriname, Swaziland, Togo and the Virgin Islands.

Is the country score a reliable measure of a country's perceived level of corruption?

In terms of perceptions of corruption, the CPI is a solid measurement tool. The reliability differs, however, between countries. Countries with a low number of sources and large differences in the values provided by the sources (indicated by a large Standard Deviation) convey less reliability as to their score and ranking.

Are old surveys used in the CPI?

The CPI is based on 2001-2003 data. Since fundamental changes in the levels of corruption in a country evolve only slowly, while public perceptions may change more swiftly and be influenced to some extent by short-term events, TI determined to base the CPI on a three-year rolling average. Hence, this year's CPI is based on survey data provided exclusively between 2001 and 2003.

Which sources have contributed to the assessment of each individual country?

A list of sources and surveys from which the CPI is derived follows at the end of the press release. A list of the sources that contributed to the assessment of each country is available on the Internet as an Excel sheet ( or This list also provides further information on standard errors and confidence intervals for each country.

Can data from one year be compared with that from a previous year?

Comparisons to the results from previous years should be based on a country's score, not its rank. A country's rank can change simple because new countries enter the index and others drop out. A higher score is an indicator that respondents provided better ratings, while a lower score suggests that respondents revised their perception downwards. However, year-to-year comparisons of a country's score do not only result from a changing perception of a country's performance but also from a changing sample and methodology. Some sources are not updated and must be dropped, while new, reliable sources are added. With differing respondents and slightly differing methodologies, a change in a country's score may also relate to the fact that different viewpoints have been collected and different questions been asked. The index primarily provides an annual snapshot of the views of businesspeople and country analysts, with less of a focus on year-to-year trends.

Which countries' scores deteriorated most between 2002 and 2003?

Making comparisons from one year to another is problematic. However, to the extent that changes can be traced back to a change in the results from individual sources, trends can be cautiously identified. Noteworthy examples of a downward trend are Argentina, Belarus, Chile, Canada, Israel, Luxembourg, Poland, USA, and Zimbabwe. The considerable decline in their scores does not result from technical factors - actual changes in perceptions are therefore likely.

Which countries improved most compared with last year?

With the same caveats applied, on the basis of data from sources that have been consistently used for the index, improvements can be observed for Austria, Belgium, Colombia, France, Germany, Ireland, Malaysia, Norway and Tunisia.