Traditionally, a nation’s economic health is measured by its wealth. But increasingly, some leaders and policymakers are turning their focus to a more human notion of well-being: happiness.

That’s the motivation behind the World Happiness Report, an analysis published by the Sustainable Development Solutions Network, a UN organization that aims to fight poverty by stoking sustainable development. The annual rankings, first published in 2012, aim to quantify happiness using Gallup World Poll data that asked people to evaluate the quality of their own lives on a scale of zero to 10. Here, based on that metric, are this year’s 25 happiest countries:

The happiest countries in the world according to the 2015 World Happiness Report

And here are the least-happy countries:

The report also attempts to attribute the differences in rankings to differences in six variables: GDP per capita, life expectancy, social support systems, trust in government and business, perceived freedom, and generosity. Charts showing the derived breakdown can be found in the full report (pdf).

This story originally appeared on Quartz, a Skift content partner.

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Photo Credit: People in Bern, Switzerland on August 13, 2011. Peter Szabo / Flickr.com