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The TAG data book provides all of the appraisal and modelling values referred to in TAG guidance. The data book features historical information and factual reference information about the appraisal and modelling values.
The previous version, TAG Data Book v1.20.1, was released in November 2022.
TAG provides information on the role of transport modelling and appraisal, and how the transport appraisal process supports the development of investment decisions to support a business case.
Published 29 November 2018 Last updated 19 April 2023 +show all updates
Added forthcoming change: spring 2023 data book and guidance updates.
TAG data book updated.
TAG data book updated.
Forthcoming changes for November 2022.
Tables A1.3.11 and A1.3.12 in 'TAG data book: fleet assumptions' have been corrected to reflect the addition of electric PSV energy consumption parameters.
Updated TAG data book. Added data book: fleet assumptions, and a forthcoming change note on fleet assumptions.
Forthcoming change to guidance note added, the note details guidance alterations to be implemented in May 2022.
Updated TAG data book.
Notification of forthcoming change for November 2021.
Added forthcoming change data book with updated carbon values and marginal external costs.
Added latest version of TAG data book and removed sensitivity testing document.
