The rankings are based on a point scoring index, which sees Zurich scoring 108, while Baghdad scores 13.5. Cities are compared to New York as the base city, with an index score of 100. The quality of living survey covers 215 cities and is conducted to help governments and major companies place employees on international assignments.
Mercer's study is based on detailed assessments and evaluations of 39 key quality of living determinants, grouped in the following categories:
Political and social environment (political stability, crime, law enforcement, etc)
Economic environment (currency exchange regulations, banking services, etc)
Socio-cultural environment (censorship, limitations on personal freedom, etc)
Health and sanitation (medical supplies and services, infectious diseases, sewage, waste disposal, air pollution, etc)
Schools and education (standard and availability of international schools, etc)
Public services and transportation (electricity, water, public transport, traffic congestion, etc)
Recreation (restaurants, theatres, cinemas, sports and leisure, etc)
Consumer goods (availability of food/daily consumption items, cars, etc)
Housing (housing, household appliances, furniture, maintenance services, etc)
Natural environment (climate, record of natural disasters)