England and Wales decile registry ew-v1 — 12 October 2026

35,672 LSOA2021 rows; 33,755 England + 1,917 Wales. Feature deciles, not risk scores.
D1 is the lowest feature value; D10 the highest. Z means observed zero for sparse features; P1–P10 are deciles of positive values. CSV band is 0 for Z, 1–10 for D/P. The feature dictionary identifies the scheme. Empty numeric cells are unavailable, not zero.
No collision or mileage data enters construction. No insurer prediction is validated. Retrospective mixed vintages: Census 2021, OS April 2026, frost normal 1991–2020. Do not backdate source availability.

Reproduce decile outputs (Python 3.10+, standard library):
  Unzip reproduce-ew-v1.zip into an empty directory.
  python scripts/build-ew-deciles.py --out-dir regenerated
  Compare regenerated/manifest.json outputs with the supplied manifest.json.
The bundle contains the source members, frozen aggregate inputs and scripts at their expected paths. No live downloads are used.
Rebuild spatial aggregates separately using build-ew-road-features.py with the pinned OS/ONS source ZIPs documented in road-source-register.json and the archived Met Office grid. This requires numpy, pandas, shapely, pyogrio, geopandas and pyarrow; exact executed versions are recorded. The two geometry ZIPs are not included in the compact bundle.

All Census denominators come from the same table as their numerator. Source category headers and formulas are in feature-dictionary.json. Cross-table disclosure-control differences are retained.
OS mapped physical roads include restricted/private roads. Road length is not motor mileage. Sinuosity is a generalised shape proxy. Air frost is not road-surface ice.
Terrain, claimants, harmonised deprivation, all-road traffic composition, schools/stops and additional weather require the gates recorded in the dictionary. Nationwide mileage-weighted summaries await Phase 3.
Attribution: ONS Census 2021 and geography; OS data © Crown copyright and database right 2026; Met Office data. Open Government Licence v3.0. See source registers for original URLs, editions and checksums.