Users should note that revisions are to be expected while the Claimant Count series is experimental and improvements are being made to the process. The experimental Claimant Count series is subject to three types of revisions.
1) Monthly revisions due to updated information
The JSA element of the Claimant Count is not revised once the data is extracted from the administrative system. The Universal Credit element however, is subject to revisions. To date revisions in the Universal Credit data have been due to issues with the geographical processing of statistical information. For example September 2018’s Claimant Count total was revised upwards by 1,100 when records that were not geographically matched were added into the revised count in the following month. This type of revision affects both the unadjusted and seasonally adjusted series.
2) Monthly revision to seasonally adjusted data
Seasonally adjusted estimates are revised on a regular basis. Each month the previous estimate is revised in line with the current seasonal adjustment model, giving the best estimate of change for the latest period. These revisions affect only the previous month's seasonally adjusted data.
3) Annual revisions to seasonally adjusted data
A seasonal adjustment review takes place once a year. Typically, the last 3 years are revised in April and published in May as part of the seasonal adjustment review. This takes the most recent year of data into account when determining the seasonal adjustment model. These revisions affect only the seasonally adjusted data.