Defined model
No reported injury collision over a 20 km car trip
- Probability:
- (100 − 6.01 × 10⁻⁴)%
- Odds:
- 166,000 to 1
- dBan
- +52.2 dBan
At Great Britain’s 2025 national rate, about 166,000 of every 166,001 modelled 20 km car trips avoid police-reported injury-collision involvement.
Calculation
λ = 484 / (1,000,000,000 × 1.609344) per km; p = e^(−λ × 20) ≈ 0.9999939851
Assumptions
This defined model applies a constant-distance Poisson rate to one 20 km car trip. The national aggregate excludes property-only and unreported collisions. It describes vehicle involvement, not every kind of incident or mechanical problem. The chosen distance is illustrative. Road, traffic, driver, and weather conditions vary.
Sources
- UK Department for Transport: vehicles involved in reported road collisions, 2025 Table 2: 484 car involvements per billion vehicle miles, published 30 July 2026