The UK-based New Economics Foundation published the Happy Planet Index (HPI) 2009 on July 4 with Costa Rica winning the title as the happiest and most environmentally friendly country, according to a report by Hong Kong’s Wen Wei Po. Latin American countries occupied nine of the top 10 positions on the list. Chinese mainland ranks 20th, and Hong Kong 84th. The US ranks 114th, with its HPI lower than Iraq and Iran.

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Also, a survey conducted by Peking University shows that the Chinese people are happier, but the degree of sense of happiness varies among rural and urban residents as well as groups of different age, education and profession. In the eyes of the Chinese, the survey indicates, psychological and physical health, harmonious family and stable marriage (or be in love) are the top three factors to happiness.