Every year, the Legatum Institute, a London-based think tank, releases its annual global Prosperity Index, a huge survey that ranks the most prosperous countries in the world.

The amount of money a country has is one factor of prosperity, but the Legatum Institute considers more than that in its ranking.

The organisation compares 89 variables to come up with its list. These variables include traditional indicators like per capita gross domestic product and the number of people in full-time work as well as more interesting figures such as the number of secure internet servers a country has and how well rested people feel on a day-to-day basis.

The variables are then split into eight subindexes: economy, entrepreneurship and opportunity, governance, education, health, safety and security, personal freedom, and social capital.

The index looked at the 142 countries that have the most available data. Here are the top-performing nations.

16. Austria — Finishing inside the top 10 in two categories — health, and entrepreneurship and opportunity — wasn't enough to stop Austria from sliding one place this year.

15. United Kingdom — Britain fell two places this year, in part by finishing outside the top 20 in the education and safety indexes.

The skyline of the City of London (Oli Scarff/Getty Images)

14. Germany — According to the Prosperity Index, Germany has the fifth-best economy in the world, helping it stay 14th for the fourth year running.

13. Luxembourg — Citizens enjoy high levels of personal freedom and health, as well as strong governance and a good economy, helping it rise from 16th in 2014 to 13th this year.

12. Iceland — The north Atlantic nation finished in the top five in three subindexes: personal freedom, safety and security, and entrepreneurship and opportunity. This wasn't enough to stop it from falling one place from the 2014 index.

Spend a day in Reykjavik and lower your APD liability (Getty Images)

11. United States — The world's most powerful country scored higher than any other in the Legatum Institute's health category, but its citizens are among the least safe and secure on this list. The USA was 33rd in this subindex.

10. Ireland — Ireland jumped two places in this year's index, thanks to finishing fourth in safety and security.

9. Finland — The Finnish enjoy the fifth-best performance of governance in the world, but their relatively poor economy, ranked 33rd, has helped push the country down from eighth last year.

8. Netherlands — Gaining one place in this year's index, the Netherlands is ranked highly in education, health, and personal freedom.

7. Australia — The country has ranked seventh for three consecutive years, and this year the Prosperity Index rated it as having the world's best education system.

An image of an indigenous Australian man is projected onto the sails of the Sydney Opera House during the opening night of the annual Vivid Sydney light festival in Sydney (Reuters)

6. Canada — According to the Prosperity Index, Canada is the true land of the free, as its citizens enjoy the highest levels of personal freedom of any nation surveyed. It fell one place from last year.

5. Sweden — Swedes are blessed with the world's highest levels of entrepreneurship and opportunity, helping the country gain one place in this year's index.

Sweden's 6 hour work day explained

4. New Zealand — Strong social cohesion and community engagement mean New Zealand has the best level of social capital on earth. It was rated the most prosperous non-European nation.

3. Denmark — Danes can enjoy great governance, top-level education, and a high social-capital score. If not for its relatively poor health score (16th), the country might top the whole Index. It climbed one place this year.

2. Switzerland — Switzerland has been second in the Prosperity Index for three consecutive years. The Alpine nation ranks top of the governance sub-index and has the second-highest-rated economy.

1. Norway — The Scandinavian country tops the Prosperity Index once again in 2015. It has been first in each of the past seven years. Norway is the only country ranked in the top 10 of every subindex.

(Visit Norway)

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