Guidance

Common analytical scenarios databook

A selection of data tables, published alongside the TAG uncertainty toolkit, to help consider and model the common analytical scenarios.

Documents

Common analytical scenarios databook

Request an accessible format.
If you use assistive technology (such as a screen reader) and need a version of this document in a more accessible format, please email webmasterdft@dft.gov.uk. Please tell us what format you need. It will help us if you say what assistive technology you use.

Details

Detailed assumptions and inputs for modelling the common analytical scenarios (CAS) outlined within the Department for Transport’s TAG uncertainty toolkit.

The CAS databook scenario grid (SG) explains the assumptions in each scenario. It supplements the TAG databook, which should be used for all values pertaining to the core scenario.

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.

Updates to this page

Published 8 August 2022
Last updated 17 November 2023 + show all updates
  1. Error correction: correction to the values of time for the technology scenario.

  2. Updates made to marginal external costs, car costs and car and bus journey times.

  3. Corrected an error in the fuel efficiencies for the Mode-balanced Decarbonisation scenario.

  4. First published.

Sign up for emails or print this page