To demonstrate the effects of policies, it is necessary to gauge how they change the situation. That means having a starting point and then evaluating the differences. This presents a problem when the situation is not fixed and the data to describe any point in time is inevitably lagging. So any model of policy changes must grapple with using historical data to describe a point in time and interpolate into the data gaps to compile a defined situation that can be used as the basis for the evaluation. So it is with this report and its models.
The model in this report uses base survey data from 2022 and 2023, combined with more recent data points, to construct a base configuration of UK society that approximates the situation in 2025. Policy effects are mapped onto that base, measuring relative changes in 2025 terms and values.
The Prosperity 2030 programme cannot start until after a General Election to gain the democratic mandate required to engage in the degree of reform proposed, hence the 2030 proposed starting date.
Unavoidably, the report presents results in 2025 terms for changes that will happen in 2030 through 2035. So it is the relative effects, which can be expected to remain constant, that are the key outputs of the modelling.