anth-volk · Oct 28, 2026 · Oct 28, 2026
diff --git a/changelog.d/726.removed.md b/changelog.d/726.removed.md
@@ -0,0 +1,3 @@
+Constituency and local-authority result rows (`compute_uk_constituency_impacts`, `compute_uk_local_authority_impacts`, `ConstituencyImpact` and `LocalAuthorityImpact`) no longer have `x` and `y` keys, the hex-map positions copied from the area lists. A lookup CSV passed as `constituency_csv_path` or `local_authority_csv_path` may still have `x` and `y` columns; they are ignored.
+
+The packaged UK area lists no longer have `x` and `y` columns: `data/uk_geography/constituencies_2024.csv` now has `code,name,region,country` and `local_authorities_2023.csv` has `code,name`, with every row, code, name and the row order unchanged.
diff --git a/docs/outputs.md b/docs/outputs.md
@@ -297,7 +297,7 @@ microdata.
 Constituency and local-authority breakdowns group household output rows by
 dataset-provided longwise geography columns. Constituencies use
 `constituency_code_oa`; local authorities use `la_code_oa`. Optional metadata
-CSVs add names and map coordinates when available.
+CSVs add names when available. Result rows carry no map positions.
 
 ```python
 from policyengine.outputs import compute_uk_constituency_impacts

diff --git a/docs/regions.md b/docs/regions.md
@@ -90,9 +90,9 @@ national UK dataset.
 
 The package ships the area lists: the 650 parliamentary constituencies (2024
 boundaries, including Northern Ireland) and the 361 local authority districts
-(April 2023, including Ards and North Down, `N09000011`), each with a name and
-a hex-map position (`src/policyengine/data/uk_geography/`, sources in its
-`SOURCES.md`). Building these regions needs no network access.
+(April 2023, including Ards and North Down, `N09000011`), each with a name
+(`src/policyengine/data/uk_geography/`, sources in its `SOURCES.md`). The lists
+have no hex-map positions. Building these regions needs no network access.
 
 Constituency regions (`constituency/<code>`) row-filter `constituency_code_oa`
 and local-authority regions (`local_authority/<code>`) row-filter `la_code_oa`.
@@ -136,9 +136,9 @@ The functions in this section and the next are deprecated: their output is
 not disclosure-controlled.
 
 Constituency-level impacts group household output rows by the longwise
-`constituency_code_oa` column carried by the dataset. Names and map coordinates
-come from the packaged constituency list; codes it does not list use the code
-as the label.
+`constituency_code_oa` column carried by the dataset. Names come from the
+packaged constituency list; codes it does not list use the code as the label.
+Result rows carry no map positions.
 
 ```python
 from policyengine.outputs import compute_uk_constituency_impacts

diff --git a/src/policyengine/countries/uk/regions.py b/src/policyengine/countries/uk/regions.py
@@ -13,8 +13,8 @@
 default dataset. They load the dataset the certified bundle routes them to
 (``region_datasets``), and the national dataset when it routes none.
 
-Their codes, names and hex positions come from the area lists shipped with the
-package (``data/uk_geography``), so building them needs no network access.
+Their codes and names come from the area lists shipped with the package
+(``data/uk_geography``), so building them needs no network access.
 """
 
 import csv

diff --git a/src/policyengine/data/uk_geography/SOURCES.md b/src/policyengine/data/uk_geography/SOURCES.md
@@ -1,12 +1,17 @@
 # UK area lists
 
-Codes, names and hex-map positions for the UK area regions and the labels of
-geography outputs. They are not the lookup CSVs paired with the legacy
-weight matrices, whose row order indexes those matrices.
+Codes and names for the UK area regions and the labels of geography outputs.
+They are not the lookup CSVs paired with the legacy weight matrices, whose row
+order indexes those matrices.
+
+The lists carry no hex-map positions. The PolicyEngine app places areas on its
+hex maps from its own layout files; earlier versions of these lists had `x`
+and `y` columns, removed in PolicyEngine/policyengine.py#726 without changing
+any row, code, name or the row order.
 
 ## `local_authorities_2023.csv`
 
-Columns `code,name,x,y`; 361 local authority districts on the April 2023 frame:
+Columns `code,name`; 361 local authority districts on the April 2023 frame:
 296 in England, 22 in Wales, 32 in Scotland and 11 in Northern Ireland,
 including Ards and North Down (`N09000011`) and the four unitaries created on
 1 April 2023 (`E06000063`–`E06000066`), and none of the 17 districts they
@@ -16,23 +21,24 @@ replaced.
   in the United Kingdom (columns `LAD23CD`, `LAD23NM`), ONS Open Geography
   Portal item `e8b361ba9e98418ba8ff2f892d00c352`. Contains public sector
   information licensed under the Open Government Licence v3.0.
-- Hex positions: PolicyEngine's April 2023 local-authority hex layout, from
-  PolicyEngine/policyengine-sim-api
+- Built from PolicyEngine/policyengine-sim-api
   `projects/policyengine-simulation-executor/src/policyengine_simulation_executor/static_runtime_files/uk_local_authorities/`
   at commit `3ac09cf9205bc66a5809e70a634c457362d1a887`:
   - `names.csv` sha256 `9e183902e54383d56f7f311d0eaac6a9ee92522a5f21c58ce5118265ae3f1bf4`
   - `coordinates_lad23.csv` sha256 `b1489a5b0101ff6d91ef9262e992cca19b59359edb42d012c305a21a04571f64`
-- Built by joining `coordinates_lad23.csv` to `names.csv` on `code`, sorted by
-  code. The names match the ONS file exactly. Against policyengine-uk-data's
-  `local_authorities_2021.csv` (360 rows on the same frame), this adds
-  `N09000011` and replaces the shared (0, 0) placeholder of the four 2023
-  unitaries with their own hexes.
+
+  The codes are those of `coordinates_lad23.csv` (the April 2023 frame),
+  joined to `names.csv` on `code` and sorted by code; the `x` and `y` columns
+  that file supplied are no longer kept. The names match the ONS file exactly.
+  Against policyengine-uk-data's `local_authorities_2021.csv` (360 rows on the
+  same frame), this adds `N09000011`.
 
 ## `constituencies_2024.csv`
 
-Columns `code,name,x,y,region,country`; the 650 parliamentary constituencies
-of the 2024 boundaries: 543 in England, 57 in Scotland, 32 in Wales and 18 in
-Northern Ireland. Copied unchanged from PolicyEngine/policyengine-uk-data
+Columns `code,name,region,country`; the 650 parliamentary constituencies of
+the 2024 boundaries: 543 in England, 57 in Scotland, 32 in Wales and 18 in
+Northern Ireland. Copied from PolicyEngine/policyengine-uk-data
 `policyengine_uk_data/storage/constituencies_2024.csv` at commit
-`26ccdd1fd1aff6665704fda37388a86adecb5122` (sha256 `f4f35d61ffc004190c438a7e1583caefd85054f962671a00069aedd0a1b5b737`).
+`26ccdd1fd1aff6665704fda37388a86adecb5122` (sha256 `f4f35d61ffc004190c438a7e1583caefd85054f962671a00069aedd0a1b5b737`),
+with its `x` and `y` columns removed and every other value unchanged.
 Codes and names: ONS (Open Government Licence v3.0).
Original file line number	Diff line number	Diff line change
		@@ -0,0 +1,3 @@
		Constituency and local-authority result rows (`compute_uk_constituency_impacts`, `compute_uk_local_authority_impacts`, `ConstituencyImpact` and `LocalAuthorityImpact`) no longer have `x` and `y` keys, the hex-map positions copied from the area lists. A lookup CSV passed as `constituency_csv_path` or `local_authority_csv_path` may still have `x` and `y` columns; they are ignored.

		The packaged UK area lists no longer have `x` and `y` columns: `data/uk_geography/constituencies_2024.csv` now has `code,name,region,country` and `local_authorities_2023.csv` has `code,name`, with every row, code, name and the row order unchanged.