Canada ranks among the least corrupt countries in the world, while Afghanistan, North Korea and Somalia are among the most crooked, according to a new report released Wednesday by a non-profit organization that tracks political corruption.

The annual Corruption Perceptions Index by Berlin-based watchdog Transparency International ranked the public sectors of 174 countries and territories based on the data collected from over a dozen groups, including the World Bank.

According to the data, Denmark, Finland and New Zealand ranked in a three-way tie as the least corrupt countries in the world.

Bottom placeholder Somalia elected a new government in Sepember and may be on the way to better performance under a new regime led by Hassan Sheikh Mohamud.

For the sixth year in a row Canada placed in the top 10 least corrupt countries, tied for ninth with the Netherlands. Among the Americas, however, Canada was on top, ahead of Barbados and the United States.

Six European countries, including all four that make up northern Europe's Scandinavian region, cracked the top 10 list for least corrupt. Greece was the worst among European Union countries at 94th overall, but across the European continent, Ukraine was perceived as the most corrupt at 144th.

'The system needs to change'

The index is tabulated from sources dating back to 2011, before the recent wave of corruption allegations in Canada that has toppled political leaders in Quebec and Ontario.

Tyler Sommers, co-ordinator at the Canadian non-profit Democracy Watch said despite Canada's score on the corruption index, the data being used may be skewed because of lax enforcement systems.

"The system needs to change rather dramatically in Canada," Sommers said. "If we had widespread audits we would find more instances of corruption, more instances of individuals who are breaking the law, [and] so those scores, because they're based on public perception, would decrease."

Gerald Tremblay speaks at a news conference in Montreal Monday, November 5, 2012 where he announced his resignation as mayor of Montreal. (Graham Hughes/The Canadian Press)

On Nov. 30, Richard Marcotte became the third Quebec mayor in recent weeks to resign. He was arrested in April and charged with fraud, corruption, breach of trust and conspiracy by Quebec's anti-corruption task force, but had refused to step down as the mayor of Mascouche until last week.

Earlier in November, the mayors of Montreal and Laval both resigned within days of each other over allegations of corruption. Both resignations have been linked to testimony at the Charbonneau inquiry which is looking into connections between Quebec politicians and the construction industry in the province.

Joe Fontana, the mayor of London, Ont., was also charged with fraud last month following an RCMP investigation that found he misused public funds in 2005 as a federal cabinet minister and Liberal member of Parliament.

Fontana has said he refuses to step down and will remain in office while he fights to clear his name.