Port the WAS wealth imputation and regional property uprating as declarative source stages

changelog.d/681-uk-was-wealth.added.md

@@ -0,0 +1 @@
+Add the UK WAS wealth imputation and regional property-uprating source-stage layer.

packages/microcosm-build/src/microcosm/build/source_manifest.py

@@ -49,6 +49,7 @@
         "assign_clipped_normal",
         "assign_uniform_draw",
         "aggregate_person_to_benunit",
+        "allocate_within_group_waterfall",
         "allocate_zero_weight_prior_mass",
         "annualize_periodic_amounts",
         "assemble_group_entities",
@@ -91,6 +92,7 @@
         "fit_vehicle_model",
         "fit_weighted_imputer",
         "fit_weighted_qrf",
+        "fit_weighted_qrf_chain",
         "fit_weighted_qrf_stage1",
         "fit_weighted_qrf_stage2",
         "fold_into",
@@ -127,6 +129,7 @@
         "strict_read_private_table",
         "support_clip",
         "uprate",
+        "uprate_to_regional_reference",
         "verify_certified_candidate",
         "verify_pinned_hmrc_source_pair",
         "zero_when_false",

packages/microcosm-build/src/microcosm/build/uk/country_package.json

@@ -12,12 +12,14 @@
     "hmrc_income_release_gate_report.json",
     "hmrc_income_replay_report.json",
     "hmrc_income_source_stages.json",
+    "regional_land_values.json",
     "source_stages.json",
     "take_up_contract.json",
     "input_mass_reviewed_exclusions.json",
     "national_staging_build_record.json",
     "qrf_tail_reviewed_exclusions.json",
     "release_input_coverage_manifest.json",
+    "was_wealth_support_bounds.json",
     "uk_local_target_census.json"
   ]
 }

packages/microcosm-build/src/microcosm/build/uk/gates.json

@@ -109,6 +109,16 @@
       "parameters": {},
       "notes": "Every UK source-stage column declared in source_stages.json nonnegative_outputs must be finite and non-negative on the terminal frame; this makes the shared nonnegative column gate live for UK."
     },
+    {
+      "id": "uk_support",
+      "gate": "support",
+      "phase": "terminal",
+      "criticality": "release_blocking",
+      "parameters": {
+        "support_bounds_resource": "was_wealth_support_bounds.json"
+      },
+      "notes": "Every WAS-imputed wealth output must remain inside the committed disclosure-safe donor support bounds. Exact donor ranges are used in-run for clipping; this release gate uses outward-rounded reviewed bounds so unit-record WAS minima and maxima are never committed."
+    },
     {
       "id": "uk_export_surface",
       "gate": "export_surface",
@@ -119,6 +129,7 @@
           "benunit.child_benefit_opts_out",
           "household.bus_fare_spending",
           "household.bus_subsidy_spending",
+          "household.cash_isa",
           "household.clone_index",
           "household.constituency_code_oa",
           "household.consumer_debt",
@@ -136,6 +147,7 @@
           "household.property_purchased",
           "household.rail_usage",
           "household.region_code_oa",
+          "household.stocks_and_shares_isa",
           "person.aa_category",
           "person.age_started_or_accepted_current_education_or_training",
           "person.attends_private_school_random_draw",

packages/microcosm-build/src/microcosm/build/uk/input_mass_reviewed_exclusions.json

@@ -9,6 +9,13 @@
     "adjudication": "microcosm#630",
     "approved_on": "2026-08-17",
     "expires_on": "2027-02-17"
+   },
+   "owned_land": {
+    "reason": "Sparse heavy-tailed WAS donor column (0.7 percent weighted nonzero share) whose weighted total is dominated by a handful of large farm/estate records: the E5 stability receipt (data/ukds/acceptance/e5/owned_land_stability_receipt.json) measures a 37.7 percent national and 2.41x London swing between adjacent seeds, the same realization-variance class the archived incumbent data repo records at uk-data#448 (4.6x Wales swing across releases). Register parity at this grain is not meaningful until the whole-spine comparison; the one-month expiry enforces the end-of-workstream revisit registered on microcosm#145 (winsorised donor or separate land imputation are the candidate remedies).",
+    "approved_by": "juaristi22",
+    "adjudication": "microcosm#714",
+    "approved_on": "2026-08-19",
+    "expires_on": "2026-09-19"
    }
   }
  }

packages/microcosm-build/src/microcosm/build/uk/regional_land_values.json

@@ -0,0 +1,72 @@
+{
+  "version": 1,
+  "country": "uk",
+  "policy": "Public regional land-value reference for deterministic post-WAS property uprating.",
+  "source": {
+    "provenance": "Incumbent public regional_land_values.csv re-homed as a JSON country-package resource for Microcosm. Values combine MHCLG dwellings and ONS UK House Price Index average prices for December 2025.",
+    "citation_urls": [
+      "https://www.gov.uk/government/collections/dwelling-stock-including-vacants",
+      "https://www.ons.gov.uk/economy/inflationandpriceindices/bulletins/housepriceindex/december2025"
+    ]
+  },
+  "values": [
+    {
+      "region": "NORTH_EAST",
+      "avg_house_price": 165257,
+      "dwellings": 1280700
+    },
+    {
+      "region": "NORTH_WEST",
+      "avg_house_price": 217428,
+      "dwellings": 3441730
+    },
+    {
+      "region": "YORKSHIRE",
+      "avg_house_price": 208447,
+      "dwellings": 2530680
+    },
+    {
+      "region": "EAST_MIDLANDS",
+      "avg_house_price": 243632,
+      "dwellings": 2213820
+    },
+    {
+      "region": "WEST_MIDLANDS",
+      "avg_house_price": 246141,
+      "dwellings": 2619300
+    },
+    {
+      "region": "EAST_OF_ENGLAND",
+      "avg_house_price": 338002,
+      "dwellings": 2841060
+    },
+    {
+      "region": "LONDON",
+      "avg_house_price": 551294,
+      "dwellings": 3813790
+    },
+    {
+      "region": "SOUTH_EAST",
+      "avg_house_price": 378800,
+      "dwellings": 4138200
+    },
+    {
+      "region": "SOUTH_WEST",
+      "avg_house_price": 301226,
+      "dwellings": 2683030
+    },
+    {
+      "region": "WALES",
+      "avg_house_price": 214883,
+      "dwellings": 1476690
+    },
+    {
+      "region": "SCOTLAND",
+      "avg_house_price": 190649,
+      "dwellings": 2602545
+    }
+  ],
+  "chronicle": [
+    "2026-08-18: added for microcosm#681 E5 WAS wealth and regional property uprating."
+  ]
+}

packages/microcosm-build/src/microcosm/build/uk/release_input_coverage_manifest.json

@@ -562,6 +562,57 @@
    "spi_prior_national_household_mass_share": 0.5,
    "stage": "hmrc_spi_income",
    "status": "required_at_build"
+  },
+  "regional_property_uprating": {
+   "base_candidate_sha256": "f17306ccb2aad7ff0130be3589b560afb2e2a12a943570911cd0c77f07934833",
+   "base_candidate_tier": "frs",
+   "effective_mass_requirements": {},
+   "output_weight_kind": "importance",
+   "outputs": [],
+   "required_mass_change_reason": "E5 source-stage transform preserves household rows and typed household weights; total household mass is conserved.",
+   "rewrites": [
+    "main_residence_value",
+    "property_wealth"
+   ],
+   "source_manifest": "source_stages.json",
+   "source_manifest_sha256": "c8eba47691c3e3b4abe833b2c2816acfc091c7039df5131e3768eb4fce393eb3",
+   "source_vintages": {
+    "source": "MHCLG dwellings and ONS UK House Price Index December 2025 regional average prices.",
+    "survey": "Public regional property reference"
+   },
+   "stage": "regional_property_uprating",
+   "status": "required_at_build"
+  },
+  "was_wealth": {
+   "base_candidate_sha256": "f17306ccb2aad7ff0130be3589b560afb2e2a12a943570911cd0c77f07934833",
+   "base_candidate_tier": "frs",
+   "effective_mass_requirements": {},
+   "output_weight_kind": "importance",
+   "outputs": [
+    "owned_land",
+    "property_wealth",
+    "corporate_wealth",
+    "gross_financial_wealth",
+    "net_financial_wealth",
+    "main_residence_value",
+    "other_residential_property_value",
+    "non_residential_property_value",
+    "savings",
+    "num_vehicles",
+    "cash_isa",
+    "stocks_and_shares_isa",
+    "student_loan_balance"
+   ],
+   "required_mass_change_reason": "E5 source-stage transform preserves household rows and typed household weights; total household mass is conserved.",
+   "rewrites": [],
+   "source_manifest": "source_stages.json",
+   "source_manifest_sha256": "c8eba47691c3e3b4abe833b2c2816acfc091c7039df5131e3768eb4fce393eb3",
+   "source_vintages": {
+    "source": "Office for National Statistics Wealth and Assets Survey, UK Data Service SN 7215, DOI 10.5255/UKDA-SN-7215-20; local licensed 2006-22 household tab.",
+    "survey": "Wealth and Assets Survey round 8"
+   },
+   "stage": "was_wealth",
+   "status": "required_at_build"
   }
  },
  "reference": {