In Europe , the regional rankings emphasize the difference in living conditions between Eastern and Western Europe, although the gap is narrowing. Mexican cities are rated lowest in the region. Hong Kong is currently rated at 93. At the other extreme, cities in Vietnam and China continue to rate poorly in world terms, although conditions have improved. Indonesia's ratings have dropped back due to the recent social and political instability in the region.
Political tensions continue to affect the rankings in the Middle East .
The continuing civil war in Congo, which has resulted in thousands of casualties and the forced evacuation of expatriates, has made Brazzaville the lowest-rated city in the whole survey. Overall, the region continues to score poorly, and low ratings for personal security, social stability, and public service standards are a feature of most of the cities surveyed. About the survey The worldwide rankings list is produced from the most recent worldwide quality of living survey conducted by Mercer. Individual reports are produced for each city surveyed, but please note that there is no overall summary report available . The aim of the survey is to provide an objective, consistent, and comprehensive evaluation of the differences in quality of living in any two cities.