Accredited official statistics

Tidy Data Guide

Updated 31 July 2025

© Crown copyright 2025

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This publication is available at https://www.gov.uk/government/statistics/personal-and-stakeholder-pensions-statistics/tidy-data-guide

For full details on the data sources, definitions and methodology of this publication, please refer to the Background and Methodology.

1. What is Tidy Data?

Tidy data is a standardised way of organising and structuring a dataset in a flat CSV file. There are no formulas or formatting, which means tidy data can be easily read into tools like R, Excel and Python with little to no data cleaning required. Tidy data follows three main principles:

  • variables should have their own columns,

  • observations should have their own row,

  • each value should have its own cell

1.1 Note on Structure

In some cases, particularly tables 6, 6.1 and 6.2, the structure has prioritised user needs and clarity over strict adherence to tidy data principles.

An accompanying metadata document can be found on the landing page for further information on the data, what each column contains, and the units of measurement used.

2. How to filter the data in Excel

Follow the instructions below to apply filters to the tidy data:

  1. Open the specific CSV file in Excel

  2. Click on any of the column names in the first row

  3. Click on the “Data” tab located in the top pane

  4. Select the “Filter” button which has an image of a funnel. This will then apply drop-down arrows and interactive filters to all columns

  5. Click on the drop-down arrows by each column name to filter for the information that you need

2.1 Example case: 2023 to 2024 Gross Pension Income Tax and National Insurance Contributions (NICs) relief

To retrieve figures for the 2023 to 2024 tax year on the gross relief on pension Income Tax and NICs, you would need to perform the following steps.

  1. Open the Table 6 CSV file in Excel

  2. Follow the instructions on how to apply filters set out in Section 2

  3. Select “2023 to 2024” as the filter in the “tax_year” column

  4. Select “Total” as the filter in the “income_tax_nics” column

  5. Select “Gross relief” as the filter in the “relief_charge” column

This will leave you with the figure for Gross Pension Income Tax and National Insurance Contributions Relief for the 2023 to 2024 tax year.

3. Special characters

To ensure the tidy data remains clear and consistent with the original formats, some special characters have been preserved and introduced in the CSV files:

  • The marker “[z]” has been used to indicate when a data point is not applicable.

  • In Table 9, values containing symbols such as “<500” have been retained from the original tables to avoid misinterpretation and preserve the intended meaning.

4. Feedback

We are committed to improving the official statistics we publish. If you have any views or feedback on the tidy data in this release, please send this by email to the below address:

personaltax.statistics@hmrc.gov.uk

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