Afghanistan, North Korea and Somalia are seen as the most corrupt nations in the world, according to Transparency International's latest survey. Pictured here, a young Afghan garbage collector looks on from a landfill in Herat on November 15, 2012. 
Afghanistan, North Korea and Somalia tied last with eight points each in the survey. In Seoul, South Korea, the effigy of North Korean leader Kim Jong Un is seen during an anti-North rally commemorating the four people killed in a 2010 attack by North Korea in Yeonpyeong on November 23, 2013. 
A woman stands in the area around Sinujiif, Somalia, on November 15, 2013, after a cyclone hit the northern region in the week, killing at least 115 people, and sweeping livestock and homes into the ocean. 
A rebel fighter from the Free Syrian Army holds a position at a front line in the Salah al-Din neighbourhood of the northern Syrian city of Aleppo, on December 1, 2013. The stricken nation dropped nine points from 144th place to 168th in the index. 
Libya, Yemen, Spain, Australia, Guatemala and Madagascar were among the other countries whose scores declined significantly. In this picture, Libyan militias surrendered their Tripoli bases to the military on November, 21 2013 nearly a week after growing public anger over the presence of armed groups in the capital sparked deadly clashes. 
Police officers take part in an operation to destroy a poppy plantation in the 11 de Mayo village in Guatemala, near the border with Mexico, on November 29, 2013. 
A Yemeni girl takes part in a gathering in support with Saudi young woman Huda al-Niran outside the courthouse during her trial on November 24, 2013 in the capital Sanaa. Niran, 22, was arrested and sued after she fled from Saudi Arabia to Yemen with a Yemeni man after her family refused to let them marry, her lawyer told Human Rights Watch. 
Demonstrators hold placards and flags of the Second Spanish Republic as they take part in a protest against the government's austerity measures in Madrid on November 23, 2013. 
Australia dropped two places to ninth position with a score of 81 in the survey. Australian former minister Eddie Obeid is pictured at Beirut International Airport on June 1, 2004. 
Supporters cheer presidential candidate Robinson Jean-Louis as he takes part in a rally in downtown Antananarivo, Madagascar, on October 26, 2013, a day after the first round of the presidential election. 
Greece's score rose four points this year to 40, but remained the lowest ranking country in the European Union in 80th place on the index. Pictured here, supporters of the ultra-nationalist party Golden Dawn demonstrate outside parliament on November 30, 2013 in Athens, Greece. - Afghanistan, North Korea and Somalia are seen as the most corrupt nations in the world
- Denmark and New Zealand are seen as the least corrupt nations
- More than two thirds of the 177 countries included in the corruption index score badly
(CNN) -- Afghanistan, North Korea and Somalia are seen as the most corrupt nations in the world, according to Transparency International's latest survey, released Tuesday.
More than two thirds of the 177 countries included in the 2013 Corruption Perceptions Index scored below 50, where 0 indicates the country's public sector is seen as highly corrupt and 100 as very clean.
Denmark and New Zealand performed best with scores of 91. Afghanistan, North Korea and Somalia tied last with 8 points each.
Driving dirty money out of politics "All countries still face the threat of corruption at all levels of government, from the issuing of local permits to the enforcement of laws and regulations," said Huguette Labelle, Transparency International's Chair in a statement.
Strategic Syrian town changes hands In Syria, where 100,000 have died in a conflict which began in 2011 and has now exploded into war, people regard its public sector as increasingly corrupt.
Turning around Greece's economy The stricken nation dropped 9 points from 144th place to 168th. Libya, Yemen, Spain, Australia, Guatemala and Madagascar were among the other countries whose scores declined significantly.
Suu Kyi on ending Myanmar violence Myanmar saw the biggest improvement, rising from 5th last position in 2012 to 19 places from the bottom this year.
The change reflects the benefits of introducing more open and democratic rules after years of military rule, according to Transparency International's Asia Pacific Director, Srirak Plipat.
Myanmar also ratified an international treaty against corruption in December 2012 and the parliament approved an anti-corruption law in July, although this is yet to come into force.
While Greece's score rose four points this year to 40, but remained the lowest ranking country in the European Union in 80th place. Brunei, Laos, Senegal, Nepal, Estonia, Lesotho and Latvia also improved.
The UK jumped from 17th to 14th place with a score of 76, two points up from last year. The U.S. did not change from last year, ranking 19th with a score of 73. China's rank did not change. Australia dropped two places to 9th position with a score of 81.
The Corruption Perceptions Index is based on perceptions of corruption in public institutions like political parties, police and justice systems according to experts and business people.
Strong access to information systems and rules governing the behavior of public officials can help a country improve, while a lack of accountability and weak public institutions damages these perceptions, Transparency International said.
The organization called on public institutions and officials to be more open, adding that corruption remains notoriously difficult to investigate and prosecute.
