Scandinavia cleaned up in the latest global rankings of happiness, notching three of the top five spots in the latest United Nations report.

Denmark, Norway, Switzerland, the Netherlands and Sweden were the first five finishers in the World Happiness Report, a ranking of 156 countries issued by the U.N. Sustainable Development Solutions Network. The U.S. ranked 17; Togo was the lowest-ranked country, taking 156 place after Rwanda, Burundi, the Central African Republic and Benin.

There weren't significant shifts in the rankings from 2012, the first year the report was issued, said John Helliwell, one of the work's editors, and co-author of one of its chapters. Mr. Helliwell, of the Vancouver School of Economics at the University of British Columbia, and the Canadian Institute for Advanced Research. Denmark held on to the number-one spot, Switzerland edged into the top five and Canada fell out of the group, to sixth place, in the latest report. Mr. Helliwell noted that there often were only slight differences in countries' actual scores. For example, Finland, at 7.369, was in seventh place while Austria was in eighth, with a score of 7.369.

The rankings are based on individuals' evaluations of their lives, collected in the Gallup World Poll between 2010 and 2012. Participants were asked to evaluate their well-being based on questions such as whether they felt they had social support in times of need, if they were free to make life choices.