Census boundary evidence
Thorold — 1921 census geography (ON)
This page identifies a census boundary representation. Source-table records below retain their own reporting-unit identity and geographic qualifications.
- Map snapshot identifier
- ON151006_1921
- Source boundary identifier
- ON151006
- Census vintage
- 1921
- Source label
- Thorold
- Province code
- ON
- District label
- Welland
- Level
- csd
- Representation class
- E93_Presence
Census continuity group: Thorold
TCP UID: ON151006
Census source records
Each link states the assessment that connected the source row to this map. Name candidates remain candidates; no source statistic is silently assigned to the map.
- Thorold — 1921 · 1921_V1T16, row 3806 unique_contextual_name_candidate
- Thorold — 1921 · 1921_V1T27, row 3339 unique_contextual_name_candidate
- Thorold — 1921 · 1921_V1T38, row 3339 unique_contextual_name_candidate
Boundary intersections across censuses
These are computed polygon intersections in the equal-area CRS ESRI:102001. Fractions describe the area of the earlier and later polygons, respectively. They do not establish historical succession, and population has not been apportioned by area. All positive intersections are retained, including very small contributions.
| Other census representation | Years (earlier → later) | Overlap (m²) | Fraction of earlier area | Fraction of later area | Evidence |
|---|---|---|---|---|---|
| Grantham · 1911 | 1911 → 1921 | 0.365758835567649 | 4.5407874052006954e-09 | 3.3978203835861996e-09 | PARTIAL_OVERLAPHistorical succession verified: False |
| Louth · 1911 | 1911 → 1921 | 0.12228595574600831 | 1.4580851105051636e-09 | 1.1360100499424765e-09 | PARTIAL_OVERLAPHistorical succession verified: False |
| Crowland · 1911 | 1911 → 1921 | 0.5239804297151669 | 6.059054484433374e-09 | 4.867664733029142e-09 | PARTIAL_OVERLAPHistorical succession verified: False |
| Pelham · 1911 | 1911 → 1921 | 0.8709211848155385 | 7.074031900258798e-09 | 8.090669223808688e-09 | PARTIAL_OVERLAPHistorical succession verified: False |
| Stamford · 1911 | 1911 → 1921 | 0.4345822343716489 | 4.334107480879827e-09 | 4.037174855942237e-09 | PARTIAL_OVERLAPHistorical succession verified: False |
| Thorold · 1911 | 1911 → 1921 | 107645132.72235246 | 0.9860931213773757 | 0.9999999742732175 | APPROXIMATELY_EQUAL_EXTENTHistorical succession verified: False |
| Wainfleet · 1911 | 1911 → 1921 | 0.03587511833419492 | 1.6350843956530947e-10 | 3.3327208117970115e-10 | PARTIAL_OVERLAPHistorical succession verified: False |
| Thorold t-v · 1911 | 1911 → 1921 | 0.4159592074489278 | 1.68863213600899e-07 | 3.864170968328994e-09 | PARTIAL_OVERLAPHistorical succession verified: False |
Continuity assessments
- Thorold (1911) → Thorold (1921): supported_continuity_with_area_separation
Area separations
| Earlier area | Continuing area | Separate area | Retained fraction | Separated fraction | Comparison status |
|---|---|---|---|---|---|
| Thorold · 1911 | Thorold · 1921 | Pelham | 0.9860931213773756 | 0.0139068577933303 | later_totals_require_geographic_reconciliation |