Box sets » Forecast evaluation report - July 2025
Throughout a forecast process the OBR, in conjunction with other government departments, uses a number of approaches to understand uncertainty in our fiscal forecasts. This box set out these approaches in detail and looked at those taken when incorporating the fiscal impacts of new policy announcements.
Our March 2023 fiscal forecast had a difference across other current spending of £14.9 billion, accounting for around 40 per cent of the £39.8 billion overall difference between the March 2023 spending forecast and outturn. This box explored explanations and set out which forecast methodologies we would review as priorities.