Happy are the people of the Nordic nations — happier, in fact, than anyone else in the world. And the overall happiness of a country is almost identical to the happiness of its immigrants.

Those are the main conclusions of the World Happiness Report 2018, released Wednesday. Finland is the happiest country in the world, it found, followed by Norway, Denmark, Iceland, Switzerland, the Netherlands, Canada, New Zealand, Sweden and Australia. Though in a different order, this is the same top 10 as last year, when Norway was No. 1 and Finland was fifth.

Burundi and Central African Republic, both consumed by political violence, are the least happy countries for the second year in a row. This year, Central African Republic is slightly happier than Burundi; last year, their order was reversed.

As for the United States, it is 18th out of 156 countries surveyed — down four spots from last year’s report and five from 2016’s, and substantially below most comparably wealthy nations. Though the economy is generally strong and per capita income is high, it ranks poorly on social measures: Life expectancy has declined, suicide rates have risen, the opioid crisis has worsened, inequality has grown and confidence in government has fallen.