The index, released every second year by the Tax Justice Network, is topped by the Cayman Islands, the United States and Switzerland. The latter had topped the list for a while until this year.

The report finds that the global financial transparency has improved on average, while it also calls for sanctions against the worse performing jurisdictions such as the US, cayman Islands and the UK.

Commanding a low share in the global market of financial services, and displaying above-average transparency of its financial and legal systems, Slovenia trails the list.

Commenting on the report, Maruša Babnik of NGO Ekvilib Inštitut said that Slovenia's position at the bottom of the index was expected considering the size of the market and measures taken.

"The index gives us an insight where we have room for improvement, while it should also serve as a warning because we cannot afford to near our positions to countries such as Luxembourg, Malta, Cyprus and Ireland when it comes to transparent operations at the international level," said Babnik.

The mentioned countries rank among the index's top 30, and these along with Slovenia and some other countries are blocking the EU's progress in getting multinationals to publicly report their earnings and taxes by countries.

"By some conservative estimates, Slovenia loses around 140 million euro a year in tax revenue as a result of transfer of profits to well-known tax havens. It's in our interests to actively demand more transparency of other countries as well," said Babnik.

Vid Tomić, secretary-general of Transparency International Slovenia, commented that Slovenia was still not advocating solutions that would contribute to a more transparent international financial system.

"We expect Slovenia to actively advocate more transparency and prevention of abuse of the financial system that also takes toll on the Slovenia budget," Tomić said.

The index shows progress in automatic exchange of data between countries and registration of ownership, including beneficial owners, while progress in reporting by individual countries is negligible.