"The census is not absolutely accurate"

'The statistics provide estimates (rounded to the nearest thousand) of the usually resident population of Scotland on Census Day. It achieved an overall response rate of 94% and the National Record of Scotland says the population is estimated with 95% confidence to be accurate to within +/- 23,000 (0.44%). The figure for England and Wales was broadly similar.


(BBC News Scotland - '11 things we learned from the Scottish 2011 Census')