Mercer conducts its Quality of Living survey annually to help multinational companies and other employers compensate employees fairly when placing them on international assignments. Employee incentives include a quality-of-living allowance and a mobility premium*. Mercer’s Quality of Living Reports provide valuable information and hardship premium recommendations for over 440 cities throughout the world; the ranking covers 230 of these cities.
Mercer considers factors such as climate, disease and sanitation standards, ease of communications, and physical remoteness that can often affect the success of a foreign assignment. They also consider local political and social environment, political violence, and crime.
In South America, Montevideo (78), Buenos Aires (91), and Santiago (93) are the highest-ranked cities, whereas La Paz (156) and Caracas (179) rank lowest.
See details at: http://www.uk.mercer.com/newsroom/2015-quality-of-living-survey.html