User needs from consumer price inflation item indices and price quote microdata

Overview

Consumer price inflation (CPI) is the rate at which the prices of goods and services bought by households rise or fall, estimated by using price indices. They are a crucial component for understanding the economy’s health.

We publish our headline CPI statistics on a monthly basis, complemented by consumer price inflation item indices and price quotes microdata. These microdata are used to construct our headline consumer price indices.

They give users unprecedented access to the detailed data, such as the detailed item-level indices and prices quotes for different types of goods and services. The price quotes dataset currently includes individual prices quotes collected manually from outlets across the UK, and also includes base (or reference) prices, validity markers and stratum weights. The item indices datasets includes item-level weights and indices for each of our consumer price inflation measures.

Why your views matter

As part of our ongoing programme of quality improvements to price statistics, we are modernising our collection of prices data, making better use of data sources, methods and systems available to us. This allows us to reflect our changing economy and produce more robust and granular inflation statistics for businesses, individuals, and government.

As part of our improvements, from March 2025 we aim to introduce grocery scanner data into our headline CPI measures.

What will be changing

The introduction of these new data sources will affect the publishing of the microdata, including discontinuing quote-level microdata for the groceries market (Divisions 1 and 2 in the Classification of Individual Consumption by Purpose, or COICOP). This is because the size and structure of the new data is intrinsically different to the current dataset. For example, we will have access to data on every type of cereal bought across the month, rather than on the sample of cereal products currently collected by our price collectors on a particular day.

We will also not be able to publish detailed scanner datasets because this may disclose the identity of the major UK retailers from whom we receive the data. Our data sharing agreements with those retailers include their data remaining anonymous.  

Within groceries expenditure categories, item indices will be replaced by broader consumption segments reflecting the increased coverage of scanner data.

It’s vital that the data and statistics we provide best meet the needs of our users, and that any changes are made with consideration of how you use our data. We would like to hear from you to understand how you have used these microdata. Your feedback will inform our future publication data strategy and, in particular, where there are any new aggregate outputs that we can regularly produce to meet current user needs.

How to respond

We welcome contributions from all users of ONS consumer price statistics, particularly those who use our lower-level price quote data on a regular or ad-hoc basis. This includes but is not limited to:

• Arm’s-length bodies and other public sector institutions
• Business and retail
• Central, local government and devolved administrations
• Charities and civil society bodies
• Financial institutions
• Policy thinktanks
• Research institutes and academia

Accessibility

If you prefer a different format, or you would like to discuss your feedback, please email cpi@ons.gov.uk.

Confidentiality and data protection 

We aim to be as open as possible in our decision-making process. As part of this, we plan to publish an anonymised summary of the responses we receive. We will not publish the personal name of any respondent. Names of individuals, organisations and groups will not be linked to any comments that you give.    

Please be aware that, as a public authority, we are subject to the Freedom of Information Act and can never completely guarantee that names and responses will not be published.  We will not publish personal contact details, such as email addresses. To find out more, please read our Privacy Policy.