A new report says Canada has dropped down to 25th place in world happiness rankings, as researchers highlight heavy social media use contributing to a sharp decline in well-being among young people.

The annual report published by the Wellbeing Research Centre at the University of Oxford found that Finland is the happiest country in the world for the ninth year in a row, with other Nordic countries such as Iceland, Denmark and Sweden ranking among the top 10.

Canada slipped to 25th place after coming 18th last year, finishing behind the 23rd-ranked United States.

In the 2015 report, Canada ranked fifth but has since steadily declined, with 25th place marking its lowest ranking since the report was launched in 2012.

The report found that life evaluations among under-25-year-olds in Canada, the U.S., Australia and New Zealand have dropped significantly over the past decade, suggesting that long hours spent scrolling through social media is a key factor in that trend.

As in previous years, nations in or near zones of major conflict remain at the bottom of the rankings with Afghanistan ranked as the unhappiest country again, followed by Sierra Leone and Malawi in Africa.