General government spending as share of GDP, excluding transfers already captured under fiscal.transfer_expansion to avoid double-counting.
Rule of law as institutional substrate — contract enforcement, judicial independence, equal treatment before the law. Upstream of most other axes.
Constitutional amendment (Art. 109, 115 GG) capping federal structural deficit at 0.35% of GDP from 2016 and prohibiting new net borrowing by the Länder from 2020, with cyclical and emergency escape clauses. Enacted by the first Merkel Grand Coalition in response to post-GFC fiscal deterioration; became the binding fiscal-policy anchor through the Schwarze Null years (2014-2019) and the object of constitutional contest in the November 2023 BVerfG KTF ruling and the March 2025 Merz- era reform.
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.