I remember hearing the Psychologist, Oliver James speak about happiness and his findings were that there was a correlation between the pursuit of money, consumer goods and discontent and that was most prevalent in English speaking countries. Cultures that lived a simpler life, assuming they had the necessities, tended to be happier.
I'm always surprised when I read these lists and generally Scandinavian countries come out top, I've only been to Denmark which I liked a lot but certainly not as much as parts of southern Europe, possibly that's a personal thing for me because I have family that hail from around the Mediterranean. Maybe I've tuned into too much Scandi Noir in the past few years and should ignore the subliminal gloom that seems to be hanging in the air they are mere dramas after all. Talking of Scandi Noir and thinking of The Bridge in particular, got talking to some Danes in Copenhagen and they did warn us off crossing over to Malmo in their words "crime ridden" but possibly they were expressing a Danish bias who knows, urban areas all over the world I guess have such problems even Scandinavia.