Labour Force Survey (LFS) Reweighting Project 2009:
In 2009, the Office for National Statistics (ONS) undertook a reweighting project, whereby LFS data were reweighted using population estimates for 2009. As a result, reweighted editions of QLFS household datasets from late 2006 onwards have been deposited at the UKDA. Further information about the 2009 reweighting project is included in the documentation for the updated datasets.

Users should note that April-June quarters from 1997-2006, and October-December quarters for 2004-2005, will therefore remain weighted to 2007-2008 population figures, as covered by the 2007 reweighting project. Household datasets prior to 1997/2004 will remain weighted to Census 2001 figures or earlier; users should consult the individual datasets for details.