The Second National Population Census of the People's Republic of China (PRC), also referred to as the 1964 Chinese Census, was conducted by the People's Republic of China with a zero hour of 1 July 1964. The results of the census were not publicized and its very existence was not officially acknowledged until the early 1980s.
The 1964 census included additional information about education, occupation, and class to the information gathered by the first census concerning name, age, sex, nationality, and relationship to heads of households.
Second National Population Census of the People's Republic of China Wikipedia
The census found the total population of Mainland China in 1964 as 694,581,759.
However, the official summaries published in Chinese Sociology and Anthropology by the Chinese State Statistical Bureau in 1984 listed the 1964 population as 723,070,269. China's official Xinhua news organization continues to report this larger figure.
The census found approximately 356,520,000 men and 338,060,000 women living in China, a ratio of 105.46 to 100.
The average household size was 4.43, an increase of 1/10 person per household from the previous census. 40.69% of the population was 14 or under; 55.75% of the population was between 15 and 64; and 3.56% of the population was 65 or older.
Han Chinese accounted for approximately 654,560,000 persons (94.24% of the total). Minorities accounted for approx. 40,020,000 persons (5.76%).
127,100,000 Chinese were classified as living in cities, an urbanization rate of 18.30%.
As with the 1953 census, the accuracy of the Second National Population Census was questioned by many outside observers. The information collected about occupation and education was so unsystematic, it could not even be accurately tabulated, although the nation's illiteracy rate was recorded as 32.26% and 33.58%.