It's a reflection that moving from the mandatory questionnaire under the census to the national household survey was a change in method. All the discussion that we've had before about response rates and that sort of thing would mean that the end result would be something where you have to use caution when you are comparing to data produced under another method, the previous method. As I say, they identified that because there was a change in method. The impact was that change in method and, because there was that change in method, users would need to use caution when making comparisons.
On October 30th, 2014. See this statement in context.