Changes to methodology

Planned changes to methods

In the 2025 release of TIFF, changes will be made to backdate labour methodology to 2018 as a result of new data on the breakdown of part time workers becoming available from the June Agricultural Census. As such, estimates from 2018 onwards are currently presented as a ‘second estimate’ rather than final estimates of these figures.

Changes made in the 2024 release to methods 2018 onwards

The 2024 release of TIFF is made following the pause of this product since 2020. As a result, this publication releases for the first time results for 2021, 2022, 2023 and 2024.

In this release, and going forward, a number of changes have been made to methods between 2018 and current estimates as a result of reviewing and improving TIFF methodology, backdating these methodology changes, and due to the availability of data sources.

Changes to methods 2012 onwards

A wide-ranging review of TIFF methodology was carried out during 2012 and 2013. Thereafter more minor methodology improvements have been identified, due to improved data sources, estimations or modelling. Where such changes have been made, back series are calculated where necessary.