【reference】
Connection method between the new series (from April 2013 survey) and the old one (until March 2013 survey)

The survey method was changed from April 2013 survey and the level of the new series is differing from the old one.
Please note that we publish the coefficients only for the user reference. (The official time-series data does NOT use these link coefficients.)
They are calculated by using the examination survey results, specifically, they are calculated in the following method.

Link coefficients = (geometric mean of the results of the conventional survey * between July 2012 and March 2013) - (geometric mean of the results of the examination survey between July 2012 and March 2013)

*the conventional survey:The survey carried out by the "direct-visit and self-completion questionnaires" method

The tables show the process of the calculation method of the link coefficients.

The calculation of the link coefficients (for the original series, excluding one-person households)

The reference data series in the case of using link coefficients (original series, excluding one-person households)

 

   For further details

please contact the Department of Business Statistics, Economic and Social Research Institute, Cabinet Office.