Corruption around the world remains a deeply entrenched, global concern according to  Transparency International’s 2011 Corruption Perceptions Index (CPI)  – the world’s most credible measure of of domestic, public sector corruption.

This year, two thirds of countries covered by the index were given scores less than 5 – which means they are considered significantly corrupt.

The CPI scores countries on a scale of zero to 10, with zero indicating high levels of corruption and 10, low levels. And the most corrupt places in the world are not the most surprising. Unstable governments, often with a legacy of conflict, continue to dominate the bottom rungs of the CPI. Afghanistan and Myanmar share second to last place with a score of 1.5, with  Somalia  and  North Korea  – measured for the first time – coming in last with a score of 1.

World corruption index interactive map.The world’s most peaceful countries score the best. In the 2011 CPI,  New Zealand  is top with a score of 9.5, followed by  Denmark, Finland,  Swedenand  Singapore.

Four countries and territories besides North Korea are included for the first time: the  Bahamas,  St Lucia, St Vincent and the Grenadines, andSuriname.

Transparency  International (TI) chair Huguette Labelle says corruption remains a major global issue, highlighted by widespread demonstrations in 2011: “This year we have seen corruption on protestor’s banners be they rich or poor. Whether in a  Europe  hit by debt crisis or an Arab world starting a new political era, leaders must head the demands for better government.”

Wealth seems no easy antidote to corruption: some relatively rich countries, including Russia, fall at the bottom of the global league table. Meanwhile, some of the world’s poorer states do comparatively well: Botswana, Bhutan, Cape Verde, and Rwanda all appear among the 50 “cleanest” countries.

While the index has been published annually since 1995, TI warns against comparing scores over time, as sources for the index change each year. However, the Berlin-based NGO notes that two general trends pop out regardless: Arab Spring countries, and many Eurozone countries  ¢â‚¬“ particularly those affected by the financial crisis  ¢â‚¬“ are doing worse and worse.

Most Arab Spring countries rank in the lower half of the index, with scores below 4. Many of the lowest-scoring European countries are those hardest hit by the financial and debt crises  ¢â‚¬“ including Greece and Italy.

The UK ranks 16th, along with Austria and the Barbados, and just ahead of Belgium and Ireland. The US ranks 24th.

The Index, which is closely watched by investors, economists, and civil society campaigners, is based on expert assessments and data from 17 surveys from 13 independent institutions, covering issues such as access to information, bribery of public officials, kickbacks in public procurement, and the enforcement of anti-corruption laws. While critics note that measuring perceptions of corruption is not the same as measuring corruption itself, the latter is almost impossible to do – as the corrupt are usually keen to cover up their tracks, hard data on graft and bribery is notoriously difficult to come by.

We’ve got the full data  below. What can you do with it?

Data summary