Three of the ten most liveable cities in the world are located in Canada, according to a new report by The Economist Intelligence Unit.

A Summary of the Liveability Ranking and Overview August 2016 ranked Vancouver, Toronto and Calgary as third, fourth and fifth on the list, respectively, trailing behind Vienna, Austria, and Melbourne, Australia, which took first place.

Out of 140 global cities surveyed, those with the best scores tend to be mid-sized and situated in wealthier countries with a relatively low population density. This “can foster a range of recreational activities without leading to high crime levels or overburdened infrastructure.” Canada’s population density is 3.9 people per square kilometre.

These three Canadian cities were also ranked in the top five last year; however, the report reveals increasing instability across the world is causing volatility in the scores of many other cities. Sydney, for example, has fallen by four places, to move out of the ten most liveable cities. It seems heightened terrorism is to blame. This is also the case for Paris, which declined in rank from increasing terrorist attacks. Meanwhile, scores dropped in U.S. cities, partly due to an increasing number of clashes between police and civilians over the past two years.

The liveability rating aims to provide the best and worst living conditions to inform benchmarking perceptions of development levels and help companies assign a hardship allowance as part of expatriate relocation packages. Every city is assigned a rating of relative comfort for over 30 qualitative and quantitative factors across five broad categories: stability, healthcare, culture and environment, education, and infrastructure. Each factor in a city is rated as acceptable, tolerable, uncomfortable, undesirable or intolerable.