{
 "dataset": "building-stock",
 "title": "Building stock by era",
 "subject": "Hennepin + Ramsey · 1880–2026",
 "source": "Hennepin and Ramsey assessors, year built",
 "scope": "all property",
 "built_from": "website/api/_data/vintage_example.json",
 "read_before_quoting": "1900 is excluded: both counties write it when the year built is unknown, and counting it as real ages a neighbourhood by decades. Condominium and co-op units are counted once, as a building would be, never once per unit. The assessor records a building after it is built, so the last 2 years are incomplete by construction — the series is complete through 2024 and rows past that carry an `incomplete` flag. This is the year a building went up, not the year it was last renovated; a 1910 warehouse gutted in 2019 is a 1910 row here.",
 "licence": {
  "attribution": "Brick & Mortar — https://brickandmortar.dev/",
  "authorities": [
   "county assessors"
  ],
  "basis": "Government data held by a Minnesota state agency or political subdivision, presumed public under the Minnesota Government Data Practices Act (Minn. Stat. ch. 13) and published by the agency itself.",
  "id": "CC BY 4.0",
  "name": "Creative Commons Attribution 4.0 International",
  "url": "https://creativecommons.org/licenses/by/4.0/"
 },
 "columns": [
  {
   "key": "era",
   "label": "era"
  },
  {
   "key": "buildings",
   "label": "buildings"
  },
  {
   "key": "share_pct",
   "label": "share"
  }
 ],
 "rows": [
  {
   "era": "before 1940",
   "buildings": 110839,
   "share_pct": 22.7
  },
  {
   "era": "1940 – 1959",
   "buildings": 119148,
   "share_pct": 24.4
  },
  {
   "era": "1960s",
   "buildings": 50141,
   "share_pct": 10.3
  },
  {
   "era": "1970s – 80s",
   "buildings": 106745,
   "share_pct": 21.8
  },
  {
   "era": "1990s",
   "buildings": 39143,
   "share_pct": 8
  },
  {
   "era": "2000 and later",
   "buildings": 63147,
   "share_pct": 12.9
  }
 ]
}