Dear Ed,
I wrote to you in October to request a temporary suspension of the accredited official statistics status for a number of Welsh Government’s statistical outputs derived from ONS’s Annual Population Survey (APS).
This was in response to the suspension of the accredited official statistics status for labour market statistics from the Labour Force Survey (LFS) in February 2024. Although the larger achieved sample on the APS for Wales means that estimates are not affected to the same extent by the quality issues experienced by the LFS, the APS sample size has fallen and the statistical uncertainty for estimates has increased. In addition, the APS has not been reweighted with more up to date population estimates and therefore it does not take account of the significant changes to the size and structure of the population as suggested by the 2021 Census.
We appreciate that ONS has a recovery plan in place for both the LFS and APS and welcome the improvements that this should bring in the future. Given the recovery plan is still in progress and the APS has not yet been reweighted, I am writing to ask you to consider a temporary suspension of the accredited official statistics status for additional sets of statistics for Wales produced from the APS. This would affect the following set of statistics:
This approach is in line with the agreement in place for other outputs based on the APS. A temporary suspension of the accreditation in Wales will therefore ensure a clear and coherent approach for users of all APS estimates until such time as the accreditation can be reinstated.
We will continue to ensure we are transparent with users on how reliable the APS estimates are. We will continue to provide appropriate advice and caveats in our publications for users of APS data and will apply suppression where appropriate.
Yours sincerely,
Stephanie Howarth
Prif Ystadegydd, Llywodraeth Cymru
Chief Statistician, Welsh Government