# CAS Auckland DSI Source Audit

Generated: 2026-06-09T06:57:10+00:00

## Coverage
- DSI crashes: 4,602
- Date range: 2018-01-01 to 2026-06-07
- Person rows: 11,761
- Vehicle rows: 7,905
- Duplicate source rows removed: {'crash': 0, 'person': 0, 'vehicle': 23251}
- Crashes missing person rows: 0
- Crashes missing vehicle rows: 0

## Useful New Measures
- Crashes with any suspected pre-crash vehicle speed: 3,357 (72.9%)
- Crashes with suspected speed for a primary contributing vehicle: 2,505
- Crashes with `Too fast for conditions = Yes`: 1,164
- DSI people: 5,109
- DSI people under 15: 307
- DSI people under 18: 575

## Recommended Use
- Keep the existing all-crash extract for total-crash outcomes.
- Use this DSI extract as the authoritative fatal/serious, person-level, and suspected-speed enrichment source for 2018 onward.
- Treat `Suspected speed before crash` as an investigator estimate, not measured operating speed.
- Compare suspected-speed availability by period and report missingness alongside speed summaries.