By Paulette Cully
Learning that China has recently completed its 2010 census of 1.3 million people and that India is in the midst of preparation for its February 2011 census of 1.2 billion people, I wanted to find out more about how one would go about counting what is in total, 37% of the world’s population. Keen to learn how this may be done, I read Len Cook’s article “The quality and qualities of population statistics, and the place of the census” in the journal “Area”. The article describes how population counts are the key to official statistical systems and the yardstick for many commercial and research surveys and analyses. In addition, the article describes how statistical offices around the world face an extensive range of challenges when counting their population, particularly because population flows have become much freer and the structure of families continue to evolve. Considering these issues, the article reviews how population counts have and will evolve over time in the UK and other countries.
In China , the decennial population Census was held between November 1 – 10, using an army of 6 million enumerators across the country. However, China has had special difficulties to overcome . Firstly, because of millions of illegal migrants, the so called “floating population”, and secondly because of the unauthorised births which were previously concealed due to the government’s stringent population policy. Some light should also be shed on the countrys’ skewed sex ratio at birth due to the preference for male offspring. There are officially about 120 male births to every 100 female instead of the global norm of 105. The official estimate of the sex ratio of the country’s 0- to-4 age group in 2008 was 123 males per 100 females.
The results of the census counts in China and India will be released at almost the same time in 2011 with India releasing their figures at the end of March and China at the end of April. Depending on the results a world population of 7 billion may be official by early next year.

Click here to read more about the China and India census
