Happiness is still on a decline in America, according to a new study.

The U.N.'s World Happiness Report launched a few days ahead of International Day of Happiness, a U.N. holiday established in 2012 and celebrated around the world on March 20.

Happiness in America has continued to fall over the last several years. Since the U.N.'s first report in 2012, the nation has dropped seven spots on the list and four spots since last year.

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To determine the results, researchers examined the answers to a specific question from the 2015-17 Gallup World Poll, a popular survey with about 3,000 respondents from 156 different countries.

Please imagine a ladder with steps numbered from zero at the bottom to 10 at the top. Suppose we say that the top of the ladder represents the best possible life for you, and the bottom of the ladder represents the worst possible life for you. On which step of the ladder would you say you personally feel you stand at this time, assuming that the higher the step the better you feel about your life, and the lower the step the worse you feel about it? Which step comes closest to the way you feel?

The questionnaire also asks respondents to rate their lives on a scale of zero to 10 across six factors: life expectancy, generosity, social support, freedom, corruption and GDP. According to the report, these happiness measures are often used by governments, organizations and civil society to inform their policymaking decisions.

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So, what is the happiest country in the world? It’s Finland, according to the poll. It had an average score of 7.632.

The least happy on the list is Burundi, which scored an average happiness score of 2.905.

This year, the United States was No. 18 with an average happiness score of 6.886.

Analysts noted the Easterlin Paradox, which implies there is no link between economic development and overall happiness, might have been a factor in America’s results.

"Indeed, while America's income per capita has increased markedly during the past half century, several of the determinants of well-being have been in decline," the authors wrote. "Social support networks in the U.S. have weakened over time; perceptions of corruption in government and business have risen over time; and confidence in public institutions has waned."

The researchers said America has the means to address public health crises and the declining well-being, but the solution will be the “sum of individual and community based efforts.”

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