The global corruption watchdog's annual Corruption Perceptions Index (CPI) released on Wednesday says that most governments around the world are moving too slowly to curb graft and bribery despite headway in some countries compared with previous years.

Transparency International's report ranks 180 countries and territories by their perceived levels of public sector corruption according to experts and businesspeople. It uses a scale of zero to 100, where zero is highly corrupt and 100 is very clean.

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This year, the CPI found that more than two thirds of countries score below 50, with an average score of 43.

Among those countries which significantly improved their CPI score over the past couple of years were Ivory Coast, Senegal and the United Kingdom. In figures broken down according to world regions, Western Europe performed best with an average score of 66. Sub-Saharan Africa (32), Eastern Europe (34) and Central Asia (34) were those lagging farthest behind.

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"Even more alarming, the index results indicates that countries with the lowest protections for press and non-governmental organizations [NGOs] also tend to have the worst rates of corruption," the CPI report said.

At least one journalist killed every week

For the first time, Transparency International examined the relationship between corruption levels and the degree of freedom enjoyed by media and civil society groups. It found that almost all journalists killed since 2012 were killed in corrupt countries.

Based on data from the Committee to Protect Journalists, the findings show that more than 9 out of 10 journalists were killed in countries that scored 45 or less on the CPI. This means that, on average, every week at least one journalist is killed in a country that is highly corrupt.

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In addition, one in five journalists that died was covering a story about corruption. "Given current crackdowns on both civil society and the media worldwide, we need to do more to protect those who speak up," said Patricia Moreira, TI's managing director, adding that justice had never been served in the majority of these cases.

The report names Brazil as an example — a country which scores only 37 on this year's CPI. There 20 journalists died in the last six years after being targeted for their investigations into local government corruption and drug-related crimes.

Civil society under siege

It was not only the media who had been in the focus of those fostering corruption, TI said, but civil society organizations, too. Incorporating information from the World Justice Project, TI's analysis shows that most countries that score low for civil liberties also tend to score high for corruption.

"Smear campaigns, harassment, lawsuits and bureaucratic red tape are all tools used by certain governments in an effort to quiet those who drive anti-corruption efforts," said Moreira.

Therefore, TI is calling on all governments that "hide behind restrictive laws" to roll them back immediately and allow for greater civic participation.

TI Chairwoman Delia Ferreira Rubio said weak rule of law, lack of access to information, governmental control over social media and reduced citizen participation were directly linked to high levels of corruption, risking "the very essence of democracy and freedom."