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If you have citizenship in Sweden or Germany, you have one of the two most powerful passports in the world Swedes and Germans can  fly to 158 countries without ever purchasing or showing a visa.

This makes international travel cheaper and easier than it is for citizens of other countries; those from Syria and Somalia, by contrast, can only enter 31 countries without a visa.

These stark differences are revealed in the  Passport Index,  which  ranks countries  based on the number of nations where citizens can go without getting a visa. Global financial advisory firm Arton Capital compiled government data from 193 countries and six territories to create the 2016 ranking.

Sweden's and Germany's passports are the most powerful because their governments have signed more mutual agreements with other countries to allow for visa-free travel. By comparison, US citizens can go to 155 countries without a visa, which puts it behind 13 other countries on the Index.

A passport's power can fluctuate month-to-month, depending on a country's relationships with other countries. And even if no visa is required, the amount of time travelers are permitted to spend in a given place varies; for example, German citizens can go to Peru without a visa for six months, but they can go to Thailand for only 30 days visa-free.

People with Swedish passports can travel visa-free to Vietnam — a liberty citizens of the US and Germany do not have. Just 21 countries in the world can enter Vietnam visa-free.

Germany's citizens are able to go to Bahrain and Lebanon without purchasing a visa, a privilege that only 63 other countries and territories have (and the US is not one of them).

Those with German or Swedish passports still need to get a visa when going to places like China and Australia, however. China only allows citizens of 11 countries to enter without a visa — that list includes Fiji, Ecuador and Japan.

But Swedish and German citizens are lucky to have their traveling power nonetheless.

Read the original article on Business Insider. Copyright 2016. Follow Business Insider on Twitter.