The United States has fallen out of the top 20 happiest countries in the world for the first time since the World Happiness Report was first published in 2012. The report, which was released on March 20, 2024, to coincide with the United Nations' International Day of Happiness, shows that the U.S. now ranks 23rd on the list of the world's happiest countries.

The World Happiness Report is based on data from the Gallup World Poll, which measures life evaluations and emotions, including happiness, sadness, anger, worry, and stress. The report also takes into account factors such as GDP per capita, social support, healthy life expectancy, freedom to make life choices, generosity, and perceptions of corruption.

According to the report, the United States' drop in the rankings is due to a decline in the reported well-being of Americans under 30. In fact, the report found that for the U.S., Canada, Australia, and New Zealand, happiness has decreased in all age groups, but especially for the young. So much so that the young are now, in 2021-2023, the least happy age group.

The top 10 happiest countries in the world remain largely unchanged compared to the 2023 report, with Finland ranking first for the seventh year in a row. Other countries in the top 10 include Denmark, Iceland, Sweden, and Israel. Lithuania is the happiest country in the world if you only look at those under the age of 30, while Denmark is the happiest country for people who are 60 and older.

The report also noted that there is a great variety among countries in the relative happiness of the younger, older, and in-between populations. This is illustrated by the fact that some countries have large differences in happiness between the young and the old, which has changed a lot over the last dozen years.

The findings were developed through a partnership between Gallup, the Oxford Wellbeing Research Centre, the World Happiness Report's editorial board, and the United Nations' Sustainable Development Solutions Network. The data used in the report differs from other sources in some parts of the world, including in the U.S., where last May, the U.S. reported an "emerging epidemic of loneliness."

The U.S.'s drop out of the top 20 happiest countries is a significant development, and it remains to be seen how the country will respond to this news.