Progressivity of the personal income tax schedule, including top marginal rates, bracket spread, and targeted credits (EITC-equivalents).
Effective 1 January 2001 under Chapter 23 of Part II of the Tax Code, Russia replaced its progressive 12%/20%/30% personal income-tax schedule with a 13% flat rate on labour income. Paradigmatic early 21st-century flat-tax reform. Generated outsized revenue increase in 2001-2002 consistent with compliance-improvement effect alongside oil- boom labour incomes.
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.