(CNN) — Reindeer jerky, anyone? Finland is the happiest country in the world, according to the latest World Happiness Report.

Norway, last year's winner, came in second place in the 2018 report. It's followed by Denmark, Iceland and Switzerland.

The report ranks countries on six key variables that support well-being: income, freedom, trust, healthy life expectancy, social support and generosity.

"The top five countries all have almost equally high values for the six factors found to support happiness, and four of these countries -- Denmark, Switzerland, Norway and now Finland -- have been in first place in the six World Happiness Report rankings since the first report," said report co-editor John Helliwell, a professor emeritus of economics at the University of British Columbia.

"In a division with such excellent teams, changes in the top spot are to be expected," he said.

Finland also had the happiest immigrants, a special focus of this year's report.

Differences among the top five countries are small enough that jostling among the top five is expected every year.

The Netherlands came in sixth place this year, followed by Canada, New Zealand, Sweden and Australia.

In the 2018 list, the top 10 countries shifted spots compared with the 2017 report, but none dropped out of the top 10 list (which means there were no new entries this year).

Happiest immigrants in the world

The 10 happiest countries were also 10 of the top 11 spots in the rankings of immigrant happiness. (Mexico, which came in 24th place in the overall rankings, placed 10th in the immigrant happiness rankings.)

"The most striking finding of the report is the remarkable consistency between the happiness of immigrants and the locally born," said Helliwell in a news release.

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"Although immigrants come from countries with very different levels of happiness, their reported life evaluations converge towards those of other residents in their new countries," said Helliwell.

"Those who move to happier countries gain, while those who move to less happy countries lose."

The United States' ranking is dropping

The United States landed in 18th place, dropping four spots from last year.

"Governments are increasingly using indicators of happiness to inform their policy-making decisions," said economics professor Jeffrey D. Sachs, director of Columbia University's Center for Sustainable Development and report co-editor.

"US policymakers should take note. The US happiness ranking is falling, in part because of the ongoing epidemics of obesity, substance abuse and untreated depression."

Other major powers didn't crack the top 10 rankings, either. Germany came in 15th place, while the United Kingdom was 19th.

Japan came in 54th place, Russia came in 59th place and China came in 86th.

People in Burundi are unhappiest with their lives, according to the survey of 156 countries, followed by Central African Republic (155), South Sudan (154), Tanzania (153) and Yemen (152).

It began with Bhutan

The tiny country of Bhutan, which came in 97th place, brought attention to happiness as a metric for its people. Its prime minister proposed a World Happiness Day to the United Nations in 2011, which created an international focus on happiness.

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One year later, the U.N. General Assembly declared March 20 as World Happiness Day , recognizing "the relevance of happiness and well-being as universal goals and aspirations in the lives of human beings around the world and the importance of their recognition in public policy objectives."