A poll conducted by The Economist Intelligence Unit, an arm of The Economist magazine, ranks five Australian cities in the top 20 in its new liveability poll. The survey takes into account five liveability factors: health-care, stability, culture and environment, education and infrastructure. Melbourne (3rd), Perth (5th) and Sydney (9th) ranked in the top 10, with Adelaide (11th) and Brisbane (16th) in the top 20. The unit's spokesman Jon Copestake said Australian cities "represent many of the best aspects of liveability". Canadian city Vancouver came at the top of the list with a ranking of 98 percent due to its strong infrastructure, while Harare in Zimbabwe was voted the toughest due to internal conflict there.