US News and World Report ranks nations for a yearly "Best Countries" study.

It includes a global power list – a list of the world's most powerful countries based on their alliances, influence and whether the country is a leader.

The US stays in first place this year, but other countries have changed positions amid rising instability.

The US remains the world's most powerful country while others have seen their positions fall amid rising instability according to this year's global power rankings.

The rankings, published by US News and World Report, look at how the influence of a nation, as well as its political, economic, and military power.

They come as part of the media organization's annual "Best Countries" study, which evaluated 80 countries based on responses from 21,000 people.

Scroll down to see the 25 most powerful nations, according to this year's rankings.