Dear Tony,
ONS Economic Statistics Plan, Consumer Prices and UKSA Board and Panels
Thank you for your letter dated 4 September 2025 and your follow-up enquiries on 5 September.
You expressed concerns with the status of the Office for National Statistics (ONS)’s CPI and CPIH statistics as accredited official statistics. As mentioned in my letter in March 2025, we are intending to re-assess CPI and CPIH once ONS has incorporated grocery scanner data into its inflation statistics. We recognise that there are competing views about different elements of the calculation of the consumer price indices, and we are continuing to encourage ONS to improve transparency around its approach. Our thinking remains open on this issue, and we plan to discuss this with a range of users, including you and your colleagues at Better Statistics.
You referenced the need for a way for users to communicate their concerns directly to the appropriate advisory committee, particularly the two UKSA consumer prices advisory panels (the Technical and Stakeholder Panels). These advisory panels can consider issues raised by users; if this has not been your experience, please let me know and my team can follow up. Separately, you mentioned that you would like to see the prompt release of minutes for UKSA Board meetings. We have referred this request to the Board Secretariat to see what can be done.
Thank you for your comments on the ONS Plan for Economic Statistics and the additional ONS Survey Improvement and Enhancement Plan. Following the publication of OSR’s 2025 State of the Statistical System report in July, I wrote to the new ONS Director General for the Economic, Social and Environmental Group, James Benford.
While in this letter I reaffirmed that the Plan for Economic Statistics met “OSR’s immediate requirements as a plan of activities to restore confidence, ensure strategic transparency and enhance focus on the quality of data inputs”, I also agreed with your view that this represents a very ambitious programme of work, and that OSR expects further actions from ONS over the longer term to build confidence. OSR has also requested quarterly reporting of progress from ONS against the milestones. So our judgement, as set out in our public statements, remains one of wanting to see how well ONS is able to deliver on these plans.
In your follow-up email, you asked for more information about the users we spoke to for our compliance review on the transformation of CPI and CPIH. These included users from the Bank of England, HM Treasury, the Royal Statistical Society, the Trades Union Congress, the Resolution Foundation, the Northern Ireland Statistics and Research Agency and the University of Southampton.
Finally, you requested any documentation about how the ONS applies hedonic regression in its calculations of inflation measures. This information is not currently located in one place. For details on its use in private rents statistics, for example, see Section 6 of the Price Index of Private Rents Quality & Methodology Information (QMI) document. For the calculation of consumer prices inflation, in our view the best resource is the Consumer Prices Indices Technical Manual.
In our regulatory work, we have set out requirements (for example Requirement 2 in our PIPR Assessment and the recommendations in our recent CPI-CPIH Compliance Review) asking ONS to improve the way it disseminates its information about its data and methods to a range of audiences. This includes setting out end-to-end documentation outlining the complete production process.
Our requirements remain outstanding, and the example of hedonic regression which you have highlighted illustrates that ONS has more to do to address this need. Please let us know of any specific thoughts you have about what ONS could do to better communicate its approach to hedonic regression.
Yours sincerely
Ed Humpherson
Director General for OSR
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Tony Dent to Ed Humpherson: ONS Economic Statistics Plan, Consumer Prices and UKSA Board and Panels