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We’re the land of Happy Meals, the T.V. show “Happy Days”, and the song “So Happy Together.” But the U.S. is not, apparently, home to the happiest people on the planet.

According to the second annual World Happiness Report, published last week by the U.N. Sustainable Development Solutions Network, the U.S. is ranked 17th happiest on a list of 156 countries. The report has made headlines across the globe, with many journalists and readers pondering the reasons for Americans’ relatively low ranking.

The report based its happiness scores on some obvious factors such as gross domestic product (GDP) and life expectancy. But other criteria surprised us, which made us wonder if happiness is less about becoming a billionaire centenarian and more about living in a friendly community.

What’s the Deal?

The report reflects global happiness levels between 2010 and 2012 based on six categories: GDP per capita, years of healthy life expectancy, social support, perceptions of corruption, prevalence of generosity, and freedom to make life choices. Several Scandinavian nations rank high for happiness, with Denmark, Norway, Switzerland, the Netherlands, and Sweden filling out the top five.

Based on those factors, global happiness increased in the majority of countries surveyed since the last report. But, unfortunately, the U.S. happiness index actually dropped slightly.

Why It Matters

We could spend the rest of our lives speculating why Americans are getting sadder and why those Scandinavians are so damn smiley. For years, Denmark has been considered one of the happiest places to live — experts cite factors such as universal free healthcare and generous maternity and paternity leave as some of the reasons why Danes are perpetually cheery. Not so surprisingly, the happiest people in the world seem to share one simple quality: They’re all really nice. Denmark scored significantly higher than the U.S. in the areas of social support and generosity. (Note: to assess social support levels, researchers asked people specifically if they’d have someone to count on in times of trouble.)

We spoke to Claire Bulger, special assistant to Jeffrey Sachs, one of the reports’ authors, about the rankings. According to Bulger, one of the main reasons why Denmark scored so much higher than the U.S. is their high altruism rank — and it turns out acting selflessly generally makes people happierAltruism, happiness, and health: it’s good to be good. Post, S.G. Department of Bioethics, School of Medicine, Case Western Reserve University, Cleveland, Ohio, USA. International Journal of Behavioral Medicine 2005;12(2):66-77.. It’s hard to measure altruism directly, but Bulger said generosity approximates altruism pretty well. Denmark and Scandinavian countries typically have high degrees of social trust (a belief in the honesty, integrity, and reliability of others), and more cohesive societies than the U.S. does.

The Takeaway

It might be up to the U.S. government to come up with a better healthcare system. But promoting altruism as a national value is something we can probably do at the individual level. It seems like it’s up to us to figure out how to be kinder, friendlier, and generally more giving.

So give up your subway seat to a pregnant lady, help an elderly man cross the street, or try out some other cliché ways to be a nicer person — whatever makes you feel good. Here’s to a happier U.S. next year.

Got something to say? Share your thoughts in the comments below or tweet the author at @ShanaDLebowitz.