{
  "original_records": 208724,
  "current_source_records": 184552,
  "current_assessment_years": {
    "2026": 184552
  },
  "original_record_match_counts": {
    "outside_boston_scope": 28266,
    "owner_text_changed": 32195,
    "mailing_text_changed": 65937,
    "assessed_total_value_changed": 156713,
    "unique_exact_source_key": 179854,
    "owner_mail_review_queue": 72155,
    "no_current_pid_match": 580,
    "map_key_differs_or_missing": 7,
    "original_key_incomplete": 17
  },
  "matched_original_assessment_years": {
    "2023": 179854
  },
  "current_records_without_unique_original_match": 4698,
  "retrieved_at_utc": "2026-09-23T19:58:14.691550+00:00",
  "source_url": "https://data.boston.gov/dataset/e02c44d2-3c64-459c-8fe2-e1ce5f38a035/resource/ee73430d-96c0-423e-ad21-c4cfb54c8961/download/fy2026-property-assessment-data_rev.csv",
  "source_sha256": "d0b656f516162c56a92782a255c731b967bd551b3e26cf412e080fdf041791fa",
  "license_url": "http://www.opendefinition.org/licenses/odc-pddl",
  "license_id": "odc-pddl",
  "attribution": "City of Boston, Assessing Department; Property Assessment FY2026, revision published May 22, 2026.",
  "source_provider": "City of Boston",
  "source_formats": "CSV (attributes only; no new geometry)",
  "current_geometry_supplied": false,
  "scope": "Boston only (MassGIS TOWN_ID 35), not all Suffolk County municipalities. Other municipalities remain outside this comparison.",
  "match_key": "MassGIS TOWN_ID 35 + PROP_ID = Boston PID + MAP_PAR_ID = Boston GIS_ID. Both identifiers must match exactly, allowing only the documented trailing underscore on Boston identifier strings. Leading zeros are preserved.",
  "method": "Unique source keys only; both original and current matches checked for uniqueness. No address, name, fuzzy, spatial or padded-number matching. Incomplete identifiers, unmatched PIDs and map-key discrepancies remain unresolved. All original records remain in the review CSV. The separate source-location exceptions remain included unchanged.",
  "change_semantics": "Owner and mailing differences are text changes, including formatting changes, not confirmed sales, legal title, delivery validation or seller intent. Monetary comparisons ignore commas and decimal formatting; assessment differences are not market appreciation or tax bills. A zero original assessed total has no percentage difference. FY2026 is an assessment year, not current ownership verification.",
  "current_unmatched_semantics": "Current records without a unique original match are a reconciliation queue, not necessarily newly created parcels.",
  "catalog_vintage": "Mixed source fiscal years + Boston-only FY2026 assessment review",
  "dictionary_url": "https://data.boston.gov/dataset/e02c44d2-3c64-459c-8fe2-e1ce5f38a035/resource/440f72b7-bb2c-4c37-971f-c1097d155559/download/property-assessment-fy2026-data-key.pdf"
}