{
 "metadata": {
  "what": "What the October 1, 2025 revaluation did to East Hampton's home assessments, measured parcel by parcel.",
  "source": "CT Office of Policy and Management, parcel and CAMA data",
  "datasets": [
   "i7xw-titi",
   "ibe8-9i3q"
  ],
  "landing_pages": [
   "https://data.ct.gov/d/i7xw-titi",
   "https://data.ct.gov/d/ibe8-9i3q"
  ],
  "generated_by": "Data/fetch_ct_cama.py",
  "method_note": "Each property is matched to itself by parcel id across two files, one from the revaluation cycle before the reset and one from the cycle after. A parcel counts only where it is a home in both files, and a home first built in or after 2022, the year the earlier file's values were filed, is excluded, because a house that did not yet exist did not have its assessment reset. Values are assessments, 70% of appraised value (CGS 12-62a).",
  "vintage_note": "The valuation_year stamped in these files is the year they were collected, not the year of the values inside them. Each file is dated by matching its home total against OPM's published class 100 grand list; see Data/check_cama_coverage.py. This pair's step agrees with OPM's own to within 5.4%.",
  "not_a_bill_note": "This measures assessments, not bills. A bill also needs the mill rate, which a budget sets. break_even_change_pct is the bridge: a home whose assessment rose by more than that pays more, and one below it pays less, before any budget change.",
  "class_average_note": "Deciles and type medians are medians of the homes in each group. A property that moved differently from its group moved differently from these figures."
 },
 "town": "East Hampton",
 "revaluation_grand_list": 2025,
 "measured_from": {
  "dataset": "i7xw-titi",
  "revaluation_cycle": 2020,
  "vintage_grand_list_year": 2022
 },
 "measured_to": {
  "dataset": "ibe8-9i3q",
  "revaluation_cycle": 2025,
  "vintage_grand_list_year": 2025
 },
 "homes_matched": 4998,
 "aggregate": {
  "residential_factor": 1.4914,
  "break_even_change_pct": 49.1,
  "median_change_pct": 51.9,
  "p10_change_pct": 26.1,
  "p90_change_pct": 71.1,
  "share_above_break_even": 0.5708,
  "share_assessment_fell": 0.0076,
  "published_step": 1.5113,
  "step_error": 0.0132
 },
 "by_value_decile": [
  {
   "decile": 1,
   "homes": 499,
   "median_assessed_before": 89290,
   "median_change_pct": 61.7,
   "p25_change_pct": 47.9,
   "p75_change_pct": 83.2,
   "share_of_base": 0.045
  },
  {
   "decile": 2,
   "homes": 500,
   "median_assessed_before": 118965,
   "median_change_pct": 43.3,
   "p25_change_pct": 32.5,
   "p75_change_pct": 53.7,
   "share_of_base": 0.0649
  },
  {
   "decile": 3,
   "homes": 500,
   "median_assessed_before": 134090,
   "median_change_pct": 46.2,
   "p25_change_pct": 36.8,
   "p75_change_pct": 55.4,
   "share_of_base": 0.0736
  },
  {
   "decile": 4,
   "homes": 500,
   "median_assessed_before": 147495,
   "median_change_pct": 49.8,
   "p25_change_pct": 39.8,
   "p75_change_pct": 59.4,
   "share_of_base": 0.0809
  },
  {
   "decile": 5,
   "homes": 500,
   "median_assessed_before": 160025,
   "median_change_pct": 51.2,
   "p25_change_pct": 39.9,
   "p75_change_pct": 59.6,
   "share_of_base": 0.088
  },
  {
   "decile": 6,
   "homes": 499,
   "median_assessed_before": 176030,
   "median_change_pct": 54.4,
   "p25_change_pct": 42.7,
   "p75_change_pct": 62.7,
   "share_of_base": 0.0965
  },
  {
   "decile": 7,
   "homes": 500,
   "median_assessed_before": 193855,
   "median_change_pct": 53.6,
   "p25_change_pct": 43.1,
   "p75_change_pct": 62.4,
   "share_of_base": 0.1063
  },
  {
   "decile": 8,
   "homes": 500,
   "median_assessed_before": 216200,
   "median_change_pct": 54.7,
   "p25_change_pct": 44.6,
   "p75_change_pct": 62.4,
   "share_of_base": 0.1184
  },
  {
   "decile": 9,
   "homes": 500,
   "median_assessed_before": 247155,
   "median_change_pct": 55.6,
   "p25_change_pct": 47.1,
   "p75_change_pct": 61.5,
   "share_of_base": 0.1362
  },
  {
   "decile": 10,
   "homes": 500,
   "median_assessed_before": 312700,
   "median_change_pct": 46.1,
   "p25_change_pct": 26.4,
   "p75_change_pct": 55.6,
   "share_of_base": 0.1903
  }
 ],
 "by_type": [],
 "excluded": {
  "matched_parcels_not_a_home_in_both": 1044,
  "new_construction_by_year_built": 17,
  "homes_in_later_file": 5350,
  "join_key": "account_number",
  "join_match_rate": 0.9342
 }
}