A growing number of conflicts around the world has led to a decline in liveability in the world’s cities over the past five years, a survey said on Tuesday.

Since 2009, average liveability in the world has fallen, “highlighting the fact that the last five years have been characterised by heightened unrest,” said the survey by The Economist Intelligence Unit.

It noted that 51 of 140 cities surveyed have seen declines in their liveability ranking, based on stability, health care, culture and environment, education and infrastructure. These locations include Kiev in Ukraine, Tripoli in Libya and Damascus in Syria, which suffered significant declines.

Conflict was responsible for many of the lowest scores, the EIU said.

“Recent conflicts in Ukraine and the Middle East have underlined continuing fallout from a decade of destabilising events ranging from the war in Iraq to the Palestinian Intifada and the Arab Spring,” the EIU said.

“Localised instability has also affected locations like Bangkok,” it added, referring to months of political unrest that began last year in Thailand, followed by a coup in May.

Melbourne is the most liveable city in the world for the fourth consecutive year, followed by Vienna in Austria and Vancouver and Toronto in Canada, the ranking said. Three other Australian cities — Adelaide, Sydney and Perth — were among the top 10 cities in the world.

The Syrian city of Damascus was the worst of 140 cities surveyed, while other bottom countries include Dhaka in Bangladesh, Port Moresby in Papua New Guinea, Lagos in Nigeria and Karachi in Pakistan.

“Those that score the best tend to be mid-sized cities in wealthier countries with a relatively low population density,” the report said.

“This can foster a range of recreational activities without leading to high crime levels or overburdened infrastructure.”