Corporate report

GAD business critical models (HTML)

Updated 9 February 2026

GAD’s Business Critical Models

The Government Actuary’s Department uses the following business critical models:

Model name	Model description
Mantle	A pension valuation system used across GAD to calculate pension costs in respect of both past service and future accrual
Annuity generator	Tool to calculate individual and bulk annuities on a variety of different assumptions
Public service pension schemes: analysis of experience model	Tool to aid actuarial advisors in determining assumptions and communicating these to clients
Public service pension schemes: valuation results and analysis of surplus calculations	Tool for calculating the Cost Cap and Employer Contribution Rate, as well as analysis of changes since prior valuation results
Accounts roll-forward tool	Tool to roll-forward liabilities for resource accounts disclosures
Actuarial factors tools	Tools to calculate and manipulate actuarial factors such as early retirement reductions, late retirement uplifts and cash equivalent transfer values
Firefighters’ Pension Scheme commutation factors	Model to generate factors for members of the Firefighters’ Pension Scheme who exchange pension for lump sum
Police Pension Scheme commutation factors	Model to generate factors for members of the Police Pension Scheme who exchange pension for lump sum
Judicial Pensions Scheme: O’Brien 2/Miller tool	Tool to enable scheme administrators to provide pension remedy calculations for members impacted by the O’Brien 2 and Miller judgements
Bulk transfer templates	Implementation of pension valuation software to provide calculation templates used to calculate bulk transfer values under Fair Deal for NHSPS & PCSPS (GB)
Service credit model	Model for the calculation of service credits under Fair Deal
DB Consolidation	Tool to simulate outcomes across potential authorisation regimes for the consolidation of Defined Benefit (DB) pension schemes
National Insurance Funds of Great Britain and Northern Ireland	Models used in relation to work for the National Insurance Funds of Great Britain and Northern Ireland, used to project contribution income and benefit expenditure and to apportion contributions between the Funds and the National Health Service
State Pension age model	Model to determine the State Pension age changes required to meet defined criteria, such as the expected average period in retirement not exceeding a specified proportion of adult life
Pension Cost Model	Enabling DfT to model future pension costs in the Railways Pension Scheme
MPS Scheme Design Modeller	Modelling scheme design variations to allow MPS stakeholders to understand implications of implementing possible changes to the scheme structure
NHS Resolution’s IBNR provisions	Model to calculate NHS Resolution’s Incurred but not reported (IBNR) provisions for accounting purposes
NHS Resolution’s cashflow and pricing models	Models used to inform the contributions set for membership of the indemnity schemes and related budgetary interactions with DHSC
Personal Injury Discount Rate modelling	Personal Injury Discount Rate modelling: claimant outcome modelling to the rate determination in England & Wales, Scotland and Northern Ireland
EU Exit: Financial Instruments Model	Model to forecast the UK’s liability under Article 143 and 144 of the Withdrawal Agreement
Annual accounts production	Model to produce GAD’s annual resource accounts, as required by statute

Last reviewed: January 2026