Progressivity of the personal income tax schedule, including top marginal rates, bracket spread, and targeted credits (EITC-equivalents).
Two successive cuts to employee Class 1 National Insurance: from 12% to 10% on 6 January 2024 (Autumn Statement 2023) and from 10% to 8% on 6 April 2024 (Spring Budget 2024). Combined annual cost ~£20bn. Self-employed Class 4 NI rate cut from 9% to 6% and Class 2 NI abolished. Framed as a supply-side cut to tax on work, though largely offset by the ongoing freeze of income-tax thresholds (fiscal drag). Pensioners and landlords did not benefit (NI not charged on pension or rental income).
Per invariant 3, reforms are scored by what they did on each channel-separated axis, not by the party that enacted them. This fingerprint is how the policy-match engine finds historical analogues.
Explicit links are curated by the author. Inferred links are hypotheses in the library that test the same axes this policy moved — the framework's answer to "what does the data say about a policy like this?".
Ranked by axis-fingerprint overlap with this policy. Direction match bolded — those are the closest historical analogues. Shape of the match is what drives policy-outcome comparison, not the country or party label.