The population of permanent residents in Beijing exceeded 21 million by the end of 2013, the municipal bureau of statistics said.
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The figure is based on a sample survey of population last year. It showed that the population of Beijing's permanent residents reached 21.15 million, 455,000 more than that of 2012.
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According to the survey, 13.12 million people in the capital held a Beijing hukou -- or Chinese household registration, 62Â percent of the total population.
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The additional 8.03 million inhabitants are migrant workers who had been living in the city for more than half a year and who are therefore classified as permanent residents.
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The survey also demonstrated that Chaoyang District has the biggest population with 3.84 million residents. Haidian ranks second. Â