Each year, the World Happiness Report releases an annual ranking of the happiest countries in the world. For the seventh year in a row, Finland earned the top spot overall.

But for people under 30, the top ranking went to Lithuania.

I think that it can be surprising, said Junona Almonaitien , an associate professor in the health psychology department at Lithuanian University of Health Sciences. When you look from the United States, ... its somewhere near Russia, an area that is often linked to danger, she said.

Lithuania regained its independence not so long ago it was in 1990, said Antanas Kairys , an associate professor in the department of general psychology at Vilnius University. That means that young people under 30 have spent their life entirely in independent Lithuania while other age groups ... experienced the harsh reality of [the] Soviet Union.

Since then, Lithuanias economy has improved along with its national relations the country joined NATO and became a European Union member in 2004. Lithuania had a really strong transformation of its economy and society, and I think the main factor of this happiness is that Lithuania is ... strong, safe and a modern democracy, Kairys said.

But other aspects of the countrys culture and norms help fuel happiness in young people. Below, experts outline a few:

People feel a sense of opportunity.

According to Kairys, Lithuanias economic growth not only means young people have more money overall, but it creates future opportunities for them.

That means that they have they have opportunity of education, of travel, of choosing leisure activities, and, actually, if you look at the capital of Lithuania Vilnius you see young people everywhere and they are doing what they like to do, Kairys said.

Another major door-opener is education, which allows Lithuanians to learn new skills and enter different careers. We have really high level of people with a university degree or college degree, Kairys said.