Dear Grant,

Compliance review of CPI and CPIH statistics

We have completed our compliance review of the Consumer Prices Index (CPI) and the Consumer Prices Index including owner occupiers’ housing costs (CPIH) statistics against the Code of Practice for Statistics. Our review looked at how ONS is handling its transformation programme for the consumer price statistics, especially in terms of the Quality and Value pillars of the Code.

Based on the findings of the review, it is our view that, overall, the transformation programme is meeting user needs and improves on current measures. We have seen evidence of assured quality and that the new data and methods are sound and suitable. However, the review makes four recommendations for ONS to address to further support the transformation of these statistics.

The statistics retain their status as accredited official statistics. Given the significance of the changes to consumer price statistics, we have previously noted our intention to re-assess CPI and CPIH once grocery scanner data have been incorporated and embedded. Our decision to re-assess is not in response to any specific concerns about the quality of CPI or CPIH but instead seeks to ensure that we provide appropriate regulatory oversight for these key statistics following a period of significant development.

I am grateful for the positive engagement from your team throughout the review.

I am copying this letter to Michael Hardie, Deputy Director, Prices Transformation; Stephen Burgess, Deputy Director, Prices Production; and Chris Payne, Assistant Deputy Director, Head of Consumer Prices Strategy and Resilience.

Yours sincerely,

Rob Kent-Smith

Deputy Head of the Office for Statistics Regulation