Some scholars in China have calculated that the total population of China in 2016 is only 1.28 billion, which is 100 million less than the 1.38 billion announced by the National Bureau of Statistics, and the most controversial number is the population born between 1991 to 2016. Population is the foundation of the country; the population data is the basis of social, economic, political, educational, science and technology, culture, national defense, diplomacy and so on. Therefore, accurate population data is of utmost importance.