The 2000 tally put China's official population at 1.295 billion people but missed migrant workers living in cities for fewer than six months.
Since then there has been an extensive shift in the population base as tens of millions of migrant workers have poured into urban areas
looking for work. Director of the publicity for the Beijing census committee Zhang Xueyuan said yesterday: "Wherever you are living from November 1 to November 10, you will be counted."
It is the sixth time China has carried out a national census but will be the first time it will count people where they live and not where their resident certificate, or hukou, is legally registered. The change will better track the demographic changes and find the true size of China's giant cities, the populations of which up to now have been only estimates. Each census taker covers about 80 to 100 households, where about 90 per cent of householders have to answer 18 questions about home ownership, jobs and family members.
The other 10 per cent, randomly selected, take an extended 45-question survey that seeks further information on reasons for moving, unemployment and other personal details.
The main data gathered during the census is to be released at the end of April.