Website of the Department of Health

The Green Book: Guidance on the appraisal of public sector investment proposals

This replaces the 1997 guidance and the main changes are: a real discount rate of 3.5% rather than 6%; the separate identification of optimism bias; recognition of differential tax treatment between publicly and PFI funded schemes.

Two further changes are introduced:

• greater emphasis on identification, quantification and monetary valuation of benefits where feasible and practical, and
• the differential impacts of proposals on different societal groups.

Supplementary guidance on optimism bias and taxation adjustment is provided.

Whilst most of this guidance is covered by the DH's own guidance on the Green Book, the matrix for the calculation of the tax adjustment is only available in Green Book supplementary guidance.

• HM Treasury: Green Book - appraisal and evaluation in central government (opens new window)