This is the fifth edition of the global report and ranking, launched the UN Sustainable Development Solutions Network (SDSN), The ranking was compiled based on Gallup's global polls in 157 states, and respondents could mark their feeling of happiness with scores from 0, as the lowest mark to 10, the highest mark.
The median score in Denmark is 7.52, and Switzerland follows with the average mark of 7.51 and Iceland, 7.5.
The top ten happy countries include Norway, Finland, Canada, the Netherlands, New Zealand, Australia and Sweden.
Croatia's median score is 5.48, sliding 12 spots from 2015 to 74th place. Its happiness index in 2015 was 5.75.
Croatia's neighbours that scored better were Italy and Slovenia, the former finishing 50th on 5.97 and the latter 63rd on 5.77.
Those that fared worse were Serbia, which placed 86th with a score of 5.17, Bosnia and Herzegovina (87th, 5.16) , Montenegro (88th, 5.16) and Hungary (91st, 5.14).
According to the report, the unhappiest nations are Burundi, Syria, Togo, Afghanistan and Benin.
The World Happiness Report 2016 Update, which ranks 156 countries by their happiness levels, was released in Rome in advance of UN World Happiness Day, March 20.
Leading experts across fields – economics, psychology, survey analysis, national statistics, health, public policy and more – describe how measurements of well-being can be used effectively to assess the progress of nations. The reports review the state of happiness in the world today and show how the new science of happiness explains personal and national variations in happiness.