Distributions and summary statistics for a zoning category in a commune

Returns the per-parcel metric distributions, summary statistics, age cohorts, and raw scatter inputs that drive the room Aireon app. Backed by an in-memory LRU keyed on ${fso}:${cz_local} (capacity 500, TTL 1 hour).

Server-side rules:

Nulls are dropped before computing distributions and summary.
Hard outliers (above p99.5 or below p0.5 within the zone) are trimmed from distributions[*]; raw min/max stay in summary.
parcels[] is unfiltered.
other_zones lists every distinct cz_local in the same FSO except the queried one, sorted by parcel count desc.

POST

https://res.aireon.ch/res_api/zone_stats

Authorization

ResApiToken
API key in header
required

Request body JSON required

fso
integer
required
BFS commune number - matches parcel_2025_07.fso_num_2021.
cz_local
string
required
Local zoning category, e.g. "W3" or "Industrie- und Gewerbezone 2".
lang
optional
de
or
en
or
fr
or
it
Locale hint for any localisable labels. Currently echoed back as _lang.

Example request

{
  "fso": 4671,
  "cz_local": "Industrie- und Gewerbezone 2",
  "lang": "de"
}

Returns

200

Zone statistics payload.

JSON

zone
object
required
- fso
  integer
  required
- cz_local
  string
  required
- parcel_count
  integer
  required
- municipality_name
  optional
  string | null
- cz_canton
  optional
  string | null
}
other_zones
array of
object
required
Sibling cz_local values in the same FSO, sorted by parcel count desc.
- cz_local
  string
  required
- parcel_count
  integer
  required
}
distributions
object
required
Trimmed (p0.5–p99.5) per-parcel samples for each metric.
- ratio_s
  optional
  array of
  number
- gfz
  optional
  array of
  number
- bldg_height_m
  optional
  array of
  number
- bldg_floors_n
  optional
  array of
  number
}
summary
object
required
- ratio_s
  optional
  object
  Summary statistics for one metric across the zone. Computed on the raw (non-trimmed) sample; min/max are honest to the underlying data.
  
  n
  integer
  required
  min
  optional
  number | null
  max
  optional
  number | null
  p5
  optional
  number | null
  p25
  optional
  number | null
  p50
  optional
  number | null
  p75
  optional
  number | null
  p95
  optional
  number | null
  mean
  optional
  number | null
- gfz
  optional
  object
  Summary statistics for one metric across the zone. Computed on the raw (non-trimmed) sample; min/max are honest to the underlying data.
  
  n
  integer
  required
  min
  optional
  number | null
  max
  optional
  number | null
  p5
  optional
  number | null
  p25
  optional
  number | null
  p50
  optional
  number | null
  p75
  optional
  number | null
  p95
  optional
  number | null
  mean
  optional
  number | null
- bldg_height_m
  optional
  object
  Summary statistics for one metric across the zone. Computed on the raw (non-trimmed) sample; min/max are honest to the underlying data.
  
  n
  integer
  required
  min
  optional
  number | null
  max
  optional
  number | null
  p5
  optional
  number | null
  p25
  optional
  number | null
  p50
  optional
  number | null
  p75
  optional
  number | null
  p95
  optional
  number | null
  mean
  optional
  number | null
- bldg_floors_n
  optional
  object
  Summary statistics for one metric across the zone. Computed on the raw (non-trimmed) sample; min/max are honest to the underlying data.
  
  n
  integer
  required
  min
  optional
  number | null
  max
  optional
  number | null
  p5
  optional
  number | null
  p25
  optional
  number | null
  p50
  optional
  number | null
  p75
  optional
  number | null
  p95
  optional
  number | null
  mean
  optional
  number | null
}
age_cohorts
object
required
Mean, p50 and p80 of cz_util_now (utilization) per building-age cohort, widest window first. Seven precision steps: the all-years baseline plus six trailing windows (60/40/20/15/10/5 years). The 15/10/5 steps were added 2026-08-24. Windows are relative to the current year. Each cohort carries n - the narrower the window the thinner the sample, so read n before trusting a cohort mean.
- now
  optional
  object
  One age cohort of the zone, on utilization: the mean, p50 and p80 of cz_util_now (gfa_now / parcel_area, the floor-area utilization) over the same parcels, with n_cz_util_now as their sample size. mean_cz_util_now was added in v0.0.323. The deprecated mean_ratio_v (not utilization) was removed in v0.0.324.
  
  cohort_label
  string
  required
  n
  integer
  required
  p50_cz_util_now
  optional
  number | null
  Median cz_util_now (gfa_now / parcel_area) of the cohort, percentile_cont(0.5). Null when n_cz_util_now is 0.
  
  p80_cz_util_now
  optional
  number | null
  80th percentile of cz_util_now of the cohort, percentile_cont(0.8). Null when n_cz_util_now is 0.
  
  n_cz_util_now
  optional
  integer
  Parcels in the cohort with a usable cz_util_now (the sample behind the mean and the two percentiles).
  
  mean_cz_util_now
  optional
  number | null
  Mean cz_util_now (gfa_now / parcel_area) of the cohort, over the same rows as the percentiles (weight: n_cz_util_now). Null when n_cz_util_now is 0.
- last60
  optional
  object
  One age cohort of the zone, on utilization: the mean, p50 and p80 of cz_util_now (gfa_now / parcel_area, the floor-area utilization) over the same parcels, with n_cz_util_now as their sample size. mean_cz_util_now was added in v0.0.323. The deprecated mean_ratio_v (not utilization) was removed in v0.0.324.
  
  cohort_label
  string
  required
  n
  integer
  required
  p50_cz_util_now
  optional
  number | null
  Median cz_util_now (gfa_now / parcel_area) of the cohort, percentile_cont(0.5). Null when n_cz_util_now is 0.
  
  p80_cz_util_now
  optional
  number | null
  80th percentile of cz_util_now of the cohort, percentile_cont(0.8). Null when n_cz_util_now is 0.
  
  n_cz_util_now
  optional
  integer
  Parcels in the cohort with a usable cz_util_now (the sample behind the mean and the two percentiles).
  
  mean_cz_util_now
  optional
  number | null
  Mean cz_util_now (gfa_now / parcel_area) of the cohort, over the same rows as the percentiles (weight: n_cz_util_now). Null when n_cz_util_now is 0.
- last40
  optional
  object
  One age cohort of the zone, on utilization: the mean, p50 and p80 of cz_util_now (gfa_now / parcel_area, the floor-area utilization) over the same parcels, with n_cz_util_now as their sample size. mean_cz_util_now was added in v0.0.323. The deprecated mean_ratio_v (not utilization) was removed in v0.0.324.
  
  cohort_label
  string
  required
  n
  integer
  required
  p50_cz_util_now
  optional
  number | null
  Median cz_util_now (gfa_now / parcel_area) of the cohort, percentile_cont(0.5). Null when n_cz_util_now is 0.
  
  p80_cz_util_now
  optional
  number | null
  80th percentile of cz_util_now of the cohort, percentile_cont(0.8). Null when n_cz_util_now is 0.
  
  n_cz_util_now
  optional
  integer
  Parcels in the cohort with a usable cz_util_now (the sample behind the mean and the two percentiles).
  
  mean_cz_util_now
  optional
  number | null
  Mean cz_util_now (gfa_now / parcel_area) of the cohort, over the same rows as the percentiles (weight: n_cz_util_now). Null when n_cz_util_now is 0.
- last20
  optional
  object
  One age cohort of the zone, on utilization: the mean, p50 and p80 of cz_util_now (gfa_now / parcel_area, the floor-area utilization) over the same parcels, with n_cz_util_now as their sample size. mean_cz_util_now was added in v0.0.323. The deprecated mean_ratio_v (not utilization) was removed in v0.0.324.
  
  cohort_label
  string
  required
  n
  integer
  required
  p50_cz_util_now
  optional
  number | null
  Median cz_util_now (gfa_now / parcel_area) of the cohort, percentile_cont(0.5). Null when n_cz_util_now is 0.
  
  p80_cz_util_now
  optional
  number | null
  80th percentile of cz_util_now of the cohort, percentile_cont(0.8). Null when n_cz_util_now is 0.
  
  n_cz_util_now
  optional
  integer
  Parcels in the cohort with a usable cz_util_now (the sample behind the mean and the two percentiles).
  
  mean_cz_util_now
  optional
  number | null
  Mean cz_util_now (gfa_now / parcel_area) of the cohort, over the same rows as the percentiles (weight: n_cz_util_now). Null when n_cz_util_now is 0.
- last15
  optional
  object
  One age cohort of the zone, on utilization: the mean, p50 and p80 of cz_util_now (gfa_now / parcel_area, the floor-area utilization) over the same parcels, with n_cz_util_now as their sample size. mean_cz_util_now was added in v0.0.323. The deprecated mean_ratio_v (not utilization) was removed in v0.0.324.
  
  cohort_label
  string
  required
  n
  integer
  required
  p50_cz_util_now
  optional
  number | null
  Median cz_util_now (gfa_now / parcel_area) of the cohort, percentile_cont(0.5). Null when n_cz_util_now is 0.
  
  p80_cz_util_now
  optional
  number | null
  80th percentile of cz_util_now of the cohort, percentile_cont(0.8). Null when n_cz_util_now is 0.
  
  n_cz_util_now
  optional
  integer
  Parcels in the cohort with a usable cz_util_now (the sample behind the mean and the two percentiles).
  
  mean_cz_util_now
  optional
  number | null
  Mean cz_util_now (gfa_now / parcel_area) of the cohort, over the same rows as the percentiles (weight: n_cz_util_now). Null when n_cz_util_now is 0.
- last10
  optional
  object
  One age cohort of the zone, on utilization: the mean, p50 and p80 of cz_util_now (gfa_now / parcel_area, the floor-area utilization) over the same parcels, with n_cz_util_now as their sample size. mean_cz_util_now was added in v0.0.323. The deprecated mean_ratio_v (not utilization) was removed in v0.0.324.
  
  cohort_label
  string
  required
  n
  integer
  required
  p50_cz_util_now
  optional
  number | null
  Median cz_util_now (gfa_now / parcel_area) of the cohort, percentile_cont(0.5). Null when n_cz_util_now is 0.
  
  p80_cz_util_now
  optional
  number | null
  80th percentile of cz_util_now of the cohort, percentile_cont(0.8). Null when n_cz_util_now is 0.
  
  n_cz_util_now
  optional
  integer
  Parcels in the cohort with a usable cz_util_now (the sample behind the mean and the two percentiles).
  
  mean_cz_util_now
  optional
  number | null
  Mean cz_util_now (gfa_now / parcel_area) of the cohort, over the same rows as the percentiles (weight: n_cz_util_now). Null when n_cz_util_now is 0.
- last5
  optional
  object
  One age cohort of the zone, on utilization: the mean, p50 and p80 of cz_util_now (gfa_now / parcel_area, the floor-area utilization) over the same parcels, with n_cz_util_now as their sample size. mean_cz_util_now was added in v0.0.323. The deprecated mean_ratio_v (not utilization) was removed in v0.0.324.
  
  cohort_label
  string
  required
  n
  integer
  required
  p50_cz_util_now
  optional
  number | null
  Median cz_util_now (gfa_now / parcel_area) of the cohort, percentile_cont(0.5). Null when n_cz_util_now is 0.
  
  p80_cz_util_now
  optional
  number | null
  80th percentile of cz_util_now of the cohort, percentile_cont(0.8). Null when n_cz_util_now is 0.
  
  n_cz_util_now
  optional
  integer
  Parcels in the cohort with a usable cz_util_now (the sample behind the mean and the two percentiles).
  
  mean_cz_util_now
  optional
  number | null
  Mean cz_util_now (gfa_now / parcel_area) of the cohort, over the same rows as the percentiles (weight: n_cz_util_now). Null when n_cz_util_now is 0.
}
parcels
array of
object
required
Unfiltered per-parcel scatter input - egrid, parcel area, built volume, latest construction year.
- egrid
  optional
  string
- area
  optional
  number | null
- volume
  optional
  number | null
- year
  optional
  integer | null
}
_lang
optional
string | null

400

Missing or invalid fso / cz_local.

JSON

error
string
required
Human-readable error description.
message
optional
string
Optional underlying error message.

401

Missing token.

JSON

error
string
required
Human-readable error description.
message
optional
string
Optional underlying error message.

403

Wrong token.

JSON

error
string
required
Human-readable error description.
message
optional
string
Optional underlying error message.

500

Server error.

JSON

error
string
required
Human-readable error description.
message
optional
string
Optional underlying error message.