{
  "schemaVersion": 2,
  "briefingId": "UI-BRF-2026-09-22",
  "title": "UK Property Evidence Briefing",
  "releaseDate": "2026-09-22",
  "publishedAt": "2026-09-22T01:04:24.432Z",
  "geography": "United Kingdom",
  "analyticalUnit": "Release-to-release change in aggregate current record representations, interpreted alongside collection completion and official long-let measures.",
  "release": {
    "releaseId": "UI-OBS-UK-2026-09-22",
    "methodVersion": "complete-active-register-v3",
    "baselineReleaseId": "UI-OBS-UK-2026-09-09",
    "baselineDate": "2026-09-09",
    "currentDate": "2026-09-22",
    "intervalDays": 13
  },
  "maturity": {
    "releaseCount": 2,
    "minimumTrendReleases": 6,
    "stage": "release-comparison",
    "trendReady": false,
    "statement": "2 approved releases support comparison, not a market trend claim."
  },
  "national": {
    "mappedRecords": 464656,
    "mappedRecordDelta": 97874,
    "mappedRecordChangeRate": 26.68,
    "datedMarketStates": 39526283,
    "datedMarketStateDelta": 2358374,
    "datedMarketStateChangeRate": 6.35,
    "gridCompletionRate": 99.48,
    "changedCells": 2251,
    "changedCellRate": 58.5
  },
  "comparisonGate": {
    "minimumCompletion": 90,
    "maximumCompletionShift": 5,
    "minimumBaselineRecords": 20,
    "methodsComparable": true,
    "totalAreas": 361,
    "comparableAreas": 339,
    "excludedAreas": 22,
    "statement": "An area can be compared only when both releases use the same method, are at least 90% complete, completion shifts by no more than 5 percentage points and the baseline contains at least 20 allocated records."
  },
  "comparableMovements": [
    {
      "code": "E07000073",
      "name": "Harlow",
      "slug": "harlow",
      "country": "England",
      "region": "East of England",
      "baselineRecords": 29,
      "currentRecords": 75,
      "recordDelta": 46,
      "recordChangeRate": 158.62,
      "baselineCompletion": 100,
      "currentCompletion": 100,
      "completionShift": 0,
      "comparable": true,
      "measures": {
        "averageRent": 1521,
        "rentGrowth": 4,
        "salePrice": 319860,
        "priceGrowth24m": 4.1,
        "grossYield": 5.7,
        "rentPeriod": "2026-08",
        "salePeriod": "2026-07",
        "grossYieldPeriod": "2026-07"
      }
    },
    {
      "code": "E08000010",
      "name": "Wigan",
      "slug": "wigan",
      "country": "England",
      "region": "North West",
      "baselineRecords": 233,
      "currentRecords": 596,
      "recordDelta": 363,
      "recordChangeRate": 155.79,
      "baselineCompletion": 100,
      "currentCompletion": 100,
      "completionShift": 0,
      "comparable": true,
      "measures": {
        "averageRent": 746,
        "rentGrowth": 6.6,
        "salePrice": 194551,
        "priceGrowth24m": 10.1,
        "grossYield": 4.6,
        "rentPeriod": "2026-08",
        "salePeriod": "2026-07",
        "grossYieldPeriod": "2026-07"
      }
    },
    {
      "code": "S12000045",
      "name": "East Dunbartonshire",
      "slug": "east-dunbartonshire",
      "country": "Scotland",
      "region": "Scotland",
      "baselineRecords": 116,
      "currentRecords": 293,
      "recordDelta": 177,
      "recordChangeRate": 152.59,
      "baselineCompletion": 100,
      "currentCompletion": 100,
      "completionShift": 0,
      "comparable": true,
      "measures": {
        "averageRent": null,
        "rentGrowth": null,
        "salePrice": 271608,
        "priceGrowth24m": 11.2,
        "grossYield": null,
        "rentPeriod": null,
        "salePeriod": "2026-07",
        "grossYieldPeriod": "2026-07"
      }
    },
    {
      "code": "E07000118",
      "name": "Chorley",
      "slug": "chorley",
      "country": "England",
      "region": "North West",
      "baselineRecords": 155,
      "currentRecords": 369,
      "recordDelta": 214,
      "recordChangeRate": 138.06,
      "baselineCompletion": 100,
      "currentCompletion": 100,
      "completionShift": 0,
      "comparable": true,
      "measures": {
        "averageRent": 798,
        "rentGrowth": 7.1,
        "salePrice": 213246,
        "priceGrowth24m": 5.9,
        "grossYield": 4.5,
        "rentPeriod": "2026-08",
        "salePeriod": "2026-07",
        "grossYieldPeriod": "2026-07"
      }
    },
    {
      "code": "E08000038",
      "name": "Barnsley",
      "slug": "barnsley",
      "country": "England",
      "region": "Yorkshire and The Humber",
      "baselineRecords": 189,
      "currentRecords": 443,
      "recordDelta": 254,
      "recordChangeRate": 134.39,
      "baselineCompletion": 100,
      "currentCompletion": 100,
      "completionShift": 0,
      "comparable": true,
      "measures": {
        "averageRent": 696,
        "rentGrowth": 7.8,
        "salePrice": 175537,
        "priceGrowth24m": 6.9,
        "grossYield": 4.7,
        "rentPeriod": "2026-08",
        "salePeriod": "2026-07",
        "grossYieldPeriod": "2026-07"
      }
    },
    {
      "code": "E07000066",
      "name": "Basildon",
      "slug": "basildon",
      "country": "England",
      "region": "East of England",
      "baselineRecords": 114,
      "currentRecords": 267,
      "recordDelta": 153,
      "recordChangeRate": 134.21,
      "baselineCompletion": 100,
      "currentCompletion": 100,
      "completionShift": 0,
      "comparable": true,
      "measures": {
        "averageRent": 1424,
        "rentGrowth": 5.4,
        "salePrice": 367233,
        "priceGrowth24m": 6,
        "grossYield": 4.6,
        "rentPeriod": "2026-08",
        "salePeriod": "2026-07",
        "grossYieldPeriod": "2026-07"
      }
    },
    {
      "code": "E08000017",
      "name": "Doncaster",
      "slug": "doncaster",
      "country": "England",
      "region": "Yorkshire and The Humber",
      "baselineRecords": 394,
      "currentRecords": 922,
      "recordDelta": 528,
      "recordChangeRate": 134.01,
      "baselineCompletion": 100,
      "currentCompletion": 100,
      "completionShift": 0,
      "comparable": true,
      "measures": {
        "averageRent": 694,
        "rentGrowth": 5.3,
        "salePrice": 172305,
        "priceGrowth24m": 8.1,
        "grossYield": 4.8,
        "rentPeriod": "2026-08",
        "salePeriod": "2026-07",
        "grossYieldPeriod": "2026-07"
      }
    },
    {
      "code": "E07000192",
      "name": "Cannock Chase",
      "slug": "cannock-chase",
      "country": "England",
      "region": "West Midlands",
      "baselineRecords": 66,
      "currentRecords": 154,
      "recordDelta": 88,
      "recordChangeRate": 133.33,
      "baselineCompletion": 100,
      "currentCompletion": 100,
      "completionShift": 0,
      "comparable": true,
      "measures": {
        "averageRent": 867,
        "rentGrowth": 7.2,
        "salePrice": 236743,
        "priceGrowth24m": 9.7,
        "grossYield": 4.4,
        "rentPeriod": "2026-08",
        "salePeriod": "2026-07",
        "grossYieldPeriod": "2026-07"
      }
    },
    {
      "code": "E08000036",
      "name": "Wakefield",
      "slug": "wakefield",
      "country": "England",
      "region": "Yorkshire and The Humber",
      "baselineRecords": 339,
      "currentRecords": 788,
      "recordDelta": 449,
      "recordChangeRate": 132.45,
      "baselineCompletion": 100,
      "currentCompletion": 100,
      "completionShift": 0,
      "comparable": true,
      "measures": {
        "averageRent": 806,
        "rentGrowth": 5.9,
        "salePrice": 199347,
        "priceGrowth24m": 5.4,
        "grossYield": 4.8,
        "rentPeriod": "2026-08",
        "salePeriod": "2026-07",
        "grossYieldPeriod": "2026-07"
      }
    },
    {
      "code": "E08000013",
      "name": "St. Helens",
      "slug": "st-helens",
      "country": "England",
      "region": "North West",
      "baselineRecords": 180,
      "currentRecords": 417,
      "recordDelta": 237,
      "recordChangeRate": 131.67,
      "baselineCompletion": 100,
      "currentCompletion": 100,
      "completionShift": 0,
      "comparable": true,
      "measures": {
        "averageRent": 807,
        "rentGrowth": 6.6,
        "salePrice": 185154,
        "priceGrowth24m": 10,
        "grossYield": 5.2,
        "rentPeriod": "2026-08",
        "salePeriod": "2026-07",
        "grossYieldPeriod": "2026-07"
      }
    },
    {
      "code": "E07000214",
      "name": "Surrey Heath",
      "slug": "surrey-heath",
      "country": "England",
      "region": "South East",
      "baselineRecords": 149,
      "currentRecords": 345,
      "recordDelta": 196,
      "recordChangeRate": 131.54,
      "baselineCompletion": 100,
      "currentCompletion": 100,
      "completionShift": 0,
      "comparable": true,
      "measures": {
        "averageRent": 1503,
        "rentGrowth": 1.5,
        "salePrice": 457988,
        "priceGrowth24m": 3.9,
        "grossYield": 4,
        "rentPeriod": "2026-08",
        "salePeriod": "2026-07",
        "grossYieldPeriod": "2026-07"
      }
    },
    {
      "code": "E06000006",
      "name": "Halton",
      "slug": "halton",
      "country": "England",
      "region": "North West",
      "baselineRecords": 66,
      "currentRecords": 152,
      "recordDelta": 86,
      "recordChangeRate": 130.3,
      "baselineCompletion": 100,
      "currentCompletion": 100,
      "completionShift": 0,
      "comparable": true,
      "measures": {
        "averageRent": 749,
        "rentGrowth": 7.1,
        "salePrice": 194727,
        "priceGrowth24m": 10.8,
        "grossYield": 4.6,
        "rentPeriod": "2026-08",
        "salePeriod": "2026-07",
        "grossYieldPeriod": "2026-07"
      }
    }
  ],
  "coverageGains": [
    {
      "code": "E07000093",
      "name": "Test Valley",
      "slug": "test-valley",
      "country": "England",
      "region": "South East",
      "baselineRecords": 513,
      "currentRecords": 702,
      "recordDelta": 189,
      "recordChangeRate": 36.84,
      "baselineCompletion": 89,
      "currentCompletion": 100,
      "completionShift": 11,
      "comparable": false,
      "measures": {
        "averageRent": 1235,
        "rentGrowth": 6.6,
        "salePrice": 368131,
        "priceGrowth24m": -0.7,
        "grossYield": 4,
        "rentPeriod": "2026-08",
        "salePeriod": "2026-07",
        "grossYieldPeriod": "2026-07"
      }
    },
    {
      "code": "E07000043",
      "name": "North Devon",
      "slug": "north-devon",
      "country": "England",
      "region": "South West",
      "baselineRecords": 3616,
      "currentRecords": 3861,
      "recordDelta": 245,
      "recordChangeRate": 6.78,
      "baselineCompletion": 83,
      "currentCompletion": 90,
      "completionShift": 7,
      "comparable": false,
      "measures": {
        "averageRent": 846,
        "rentGrowth": -0.3,
        "salePrice": 282633,
        "priceGrowth24m": -0.9,
        "grossYield": 3.6,
        "rentPeriod": "2026-08",
        "salePeriod": "2026-07",
        "grossYieldPeriod": "2026-07"
      }
    },
    {
      "code": "W06000010",
      "name": "Carmarthenshire",
      "slug": "carmarthenshire",
      "country": "Wales",
      "region": "Wales",
      "baselineRecords": 1636,
      "currentRecords": 1967,
      "recordDelta": 331,
      "recordChangeRate": 20.23,
      "baselineCompletion": 93,
      "currentCompletion": 100,
      "completionShift": 7,
      "comparable": false,
      "measures": {
        "averageRent": 687,
        "rentGrowth": 6.6,
        "salePrice": 199025,
        "priceGrowth24m": 4.8,
        "grossYield": 4.1,
        "rentPeriod": "2026-08",
        "salePeriod": "2026-07",
        "grossYieldPeriod": "2026-07"
      }
    }
  ],
  "regions": [
    {
      "name": "East Midlands",
      "areas": 35,
      "comparableAreas": 32,
      "baselineRecords": 16783,
      "currentRecords": 22890,
      "currentCompletion": 94.3,
      "baselineCompletion": 94.1,
      "recordDelta": 6107,
      "comparableShare": 91.4
    },
    {
      "name": "East of England",
      "areas": 45,
      "comparableAreas": 41,
      "baselineRecords": 26092,
      "currentRecords": 36026,
      "currentCompletion": 96.7,
      "baselineCompletion": 96.7,
      "recordDelta": 9934,
      "comparableShare": 91.1
    },
    {
      "name": "London",
      "areas": 33,
      "comparableAreas": 26,
      "baselineRecords": 56948,
      "currentRecords": 68405,
      "currentCompletion": 88,
      "baselineCompletion": 88,
      "recordDelta": 11457,
      "comparableShare": 78.8
    },
    {
      "name": "North East",
      "areas": 12,
      "comparableAreas": 12,
      "baselineRecords": 10406,
      "currentRecords": 14577,
      "currentCompletion": 100,
      "baselineCompletion": 100,
      "recordDelta": 4171,
      "comparableShare": 100
    },
    {
      "name": "North West",
      "areas": 35,
      "comparableAreas": 33,
      "baselineRecords": 30817,
      "currentRecords": 41024,
      "currentCompletion": 97.6,
      "baselineCompletion": 97.6,
      "recordDelta": 10207,
      "comparableShare": 94.3
    },
    {
      "name": "Northern Ireland",
      "areas": 11,
      "comparableAreas": 11,
      "baselineRecords": 8941,
      "currentRecords": 9183,
      "currentCompletion": 100,
      "baselineCompletion": 100,
      "recordDelta": 242,
      "comparableShare": 100
    },
    {
      "name": "Scotland",
      "areas": 32,
      "comparableAreas": 32,
      "baselineRecords": 37155,
      "currentRecords": 45790,
      "currentCompletion": 100,
      "baselineCompletion": 99.9,
      "recordDelta": 8635,
      "comparableShare": 100
    },
    {
      "name": "South East",
      "areas": 64,
      "comparableAreas": 62,
      "baselineRecords": 42823,
      "currentRecords": 58163,
      "currentCompletion": 99.8,
      "baselineCompletion": 99.6,
      "recordDelta": 15340,
      "comparableShare": 96.9
    },
    {
      "name": "South West",
      "areas": 27,
      "comparableAreas": 26,
      "baselineRecords": 63714,
      "currentRecords": 73664,
      "currentCompletion": 99,
      "baselineCompletion": 98.7,
      "recordDelta": 9950,
      "comparableShare": 96.3
    },
    {
      "name": "Wales",
      "areas": 22,
      "comparableAreas": 21,
      "baselineRecords": 30812,
      "currentRecords": 36163,
      "currentCompletion": 100,
      "baselineCompletion": 99.6,
      "recordDelta": 5351,
      "comparableShare": 95.5
    },
    {
      "name": "West Midlands",
      "areas": 30,
      "comparableAreas": 30,
      "baselineRecords": 18222,
      "currentRecords": 26410,
      "currentCompletion": 99.7,
      "baselineCompletion": 99.7,
      "recordDelta": 8188,
      "comparableShare": 100
    },
    {
      "name": "Yorkshire and The Humber",
      "areas": 15,
      "comparableAreas": 13,
      "baselineRecords": 24069,
      "currentRecords": 32361,
      "currentCompletion": 97.8,
      "baselineCompletion": 97.8,
      "recordDelta": 8292,
      "comparableShare": 86.7
    }
  ],
  "areaFocus": [
    {
      "code": "E07000073",
      "name": "Harlow",
      "slug": "harlow",
      "country": "England",
      "region": "East of England",
      "baselineRecords": 29,
      "currentRecords": 75,
      "recordDelta": 46,
      "recordChangeRate": 158.62,
      "baselineCompletion": 100,
      "currentCompletion": 100,
      "completionShift": 0,
      "comparable": true,
      "measures": {
        "averageRent": 1521,
        "rentGrowth": 4,
        "salePrice": 319860,
        "priceGrowth24m": 4.1,
        "grossYield": 5.7,
        "rentPeriod": "2026-08",
        "salePeriod": "2026-07",
        "grossYieldPeriod": "2026-07"
      }
    },
    {
      "code": "S12000045",
      "name": "East Dunbartonshire",
      "slug": "east-dunbartonshire",
      "country": "Scotland",
      "region": "Scotland",
      "baselineRecords": 116,
      "currentRecords": 293,
      "recordDelta": 177,
      "recordChangeRate": 152.59,
      "baselineCompletion": 100,
      "currentCompletion": 100,
      "completionShift": 0,
      "comparable": true,
      "measures": {
        "averageRent": null,
        "rentGrowth": null,
        "salePrice": 271608,
        "priceGrowth24m": 11.2,
        "grossYield": null,
        "rentPeriod": null,
        "salePeriod": "2026-07",
        "grossYieldPeriod": "2026-07"
      }
    },
    {
      "code": "W06000019",
      "name": "Blaenau Gwent",
      "slug": "blaenau-gwent",
      "country": "Wales",
      "region": "Wales",
      "baselineRecords": 68,
      "currentRecords": 132,
      "recordDelta": 64,
      "recordChangeRate": 94.12,
      "baselineCompletion": 100,
      "currentCompletion": 100,
      "completionShift": 0,
      "comparable": true,
      "measures": {
        "averageRent": 681,
        "rentGrowth": 6.8,
        "salePrice": 144294,
        "priceGrowth24m": 11.3,
        "grossYield": 5.6,
        "rentPeriod": "2026-08",
        "salePeriod": "2026-07",
        "grossYieldPeriod": "2026-07"
      }
    },
    {
      "code": "N09000011",
      "name": "Ards and North Down",
      "slug": "ards-and-north-down",
      "country": "Northern Ireland",
      "region": "Northern Ireland",
      "baselineRecords": 877,
      "currentRecords": 1066,
      "recordDelta": 189,
      "recordChangeRate": 21.55,
      "baselineCompletion": 100,
      "currentCompletion": 100,
      "completionShift": 0,
      "comparable": true,
      "measures": {
        "averageRent": null,
        "rentGrowth": null,
        "salePrice": 227275,
        "priceGrowth24m": 10.7,
        "grossYield": null,
        "rentPeriod": null,
        "salePeriod": "2026-07",
        "grossYieldPeriod": "2026-07"
      }
    }
  ],
  "files": {
    "release": "/data/releases/2026-09-22/manifest.json",
    "comparison": "/data/comparisons/2026-09-09--2026-09-22.json",
    "areaLayer": "/data/area-observations/2026-09-22.json",
    "atlas": "/data/releases/2026-09-22/property-atlas.json"
  },
  "atlasSnapshotSha256": "15646fe803196945594fee5a78e6b7b0bb258c346e7ff94ee87efa0a95b7d383",
  "limitations": [
    "2 releases use the current method. At least six consistent releases are required before monitoring trends.",
    "The 18 August 2026 area layer predates the immutable national manifest series. It remains available as historical evidence but is not counted as an approved national release.",
    "Current record representations are not counts of unique homes, bookings, tenancies or complete local market inventory.",
    "Local movement can reflect collection, geolocation and identity evidence as well as changes in the current market cross-section.",
    "Long-let rent, growth, sale-price and yield measures use their separately stated official evidence periods and are not inferred from the observation layer."
  ]
}
