The Global Peace Index is currently considered the most comprehensive effort to assess which countries are the most peaceful around the world. Visions of Humanity, the group behind the GPI, releases an annual report assessing which nations are getting ahead, and which are falling behind. With the 2016 Global Peace Index due to release in a few days, lets review the 2015 index and what it told us about the world.

Iceland ranked first in the list of peaceful countries, reclaiming its top spot from last year. As might be expected, Syria remains in the bottom spot with an overall score of 3.645. Libya was the country that slipped the furthest down the index, as sectarian conflict increased in the wake of Muammar Gaddafi’s death. Ukraine also saw a steep decline since 2014.

Fighting in the Middle East, in countries like Syria, Iraq and Afghanistan, brought the overall level of peace to its lowest point since 2008, when military spending started increasing in important countries around the world.

The United States rose a couple of spots, but it’s still in the bottom half of the list, likely because it is the world’s leading military power and involved in at least two active wars.

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Top 100 Happiest and Peaceful Countries 01Top 100 Happiest and Peaceful Countries 03

Overall, the biggest detractors to peace in the 2014-2015 period were conflicts in the Middle East that forced people from their homes and caused the refugee crisis that is still ongoing. As The Guardian stated, “Providing services for refugees and internally displaced people was one of the biggest costs of last year’s violence.”

This decline in peace, the institute said, costs the world economy about $14.3-trillion, a steep rise from the $8.12-trillion of five years ago.

Top 100 Happiest and Peaceful Countries 02The index uses 23 quantitative and qualitative measures to determine the level of peace in a given country. These include military spending as a percentage of GDP, level of violent crime, likelihood of violent demonstrations, deaths from conflict and relations with neighbouring countries.