As a whole, the world became a more peaceful place in 2017, with 93 countries, including China, recording improvements in the degree of peace they enjoyed during the previous year. At the same time, 68 countries became less peaceful, according to Global Peace Index figures released on Thursday by a Australia-based think tank.

The 11th edition of the index, compiled by the Institute for Economics and Peace, found that China improved on the previous year largely because of improvements in indicators measuring deaths from internal conflict, the impact of terrorism, and the level of external conflicts. China ranked 116 out of 163 in the index, up three places on the previous year.

Iceland maintained its position as the most peaceful country in the world, followed by New Zealand and Portugal. For the fifth consecutive year, Syria was the least peaceful country in the GPI, followed by Iraq and South Sudan.

The report also found that several countries in Europe experienced a deterioration in peace, due to populist parties gaining ground in elections. The political turmoil in the United States during and following Donald Trump's presidential campaign led to North America deteriorating more than any other region in the world, in terms of its peacefulness.

Steve Killelea, founder of the IEP, said: "While the true extent of such significant political polarity in the US will take years to be fully realized, its disruptive influence is already evident. Increasing inequality, rising perceptions of corruption, and falling press freedoms have all contributed to this substantial deterioration in the US and an overall decline in peace in the North America region."

Killelea said the role of populist parties in mainstream European politics had caused persistent challenges to the free fl ow of information, levels of corruption, and acceptance of the rights of others.

While the number of deaths from terrorism globally dropped by 10 percent between 2014 and 2015, 23 countries experienced historically high levels of terrorism, which was an all-time high. Europe saw a significant rise, and terrorist attacks in France saw the country fall five places in the overall ranking, to 51. Attacks in Brussels and London were included in the data, although the recent suicide bombing in Manchester that claimed 22 lives was not.

Killelea said: "Although this year's uptick is reassuring, the world is still mired with conflict in the Middle East, political turmoil in the US, refugee flows and terrorism in Europe. When combined with the increasing level of peace inequality, whereby the least peaceful countries are moving further apart from the most peaceful, the resulting scenario is one in which further improvements in peace are not guaranteed."

During the last year, the global economic impact of violence totaled $14.3 trillion or 12.6 percent of world GDP.