For the second year in a row, the world's happiest country is... Finland!

Finland topped the list of 156 countries, which were ranked in the United Nations Sustainable Development Solutions Network's 2019 World Happiness Report. The report ranks countries on several well-being variables including income, freedom, trust, healthy life expectancy and more.

Two other Nordic countries came in second and third place, Denmark and Norway, respectively.

On the other hand, South Sudan ranked the least happy on the list.

Where does the United States fall? At No. 19, a slip from last year's 18th spot (which was already down four places from 2017).

To find out where other countries ranked on the list, click through the gallery above.

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