Driving/Data
Fatality Risk
| Distance (thousands of miles) | Fatalities per 1,000 miles |
|---|---|
|
1 |
0.0126 |
This table is based on 2023 U.S. traffic data: about 1.26 fatalities per 100 million vehicle miles traveled (VMT), which equals 0.0126 fatalities per 1,000 miles.
Injury (Serious) Risk
| Distance (thousands of miles) | Serious injuries per 1,000 miles |
|---|---|
|
1 |
0.75 |
This is based on 2022 NHTSA estimates: about 75 injuries per 100 million VMT, which equals 0.75 injuries per 1,000 miles.
Time of Day (Modifier)
| Time of day | Fatality risk multiplier | Injury risk multiplier |
|---|---|---|
|
Day |
1.0 |
1.0 |
|
Night |
3.56 |
1.47 |
Per-mile risk is higher at night because more crashes happen during the ~25% of miles driven in darkness. In 2022, about 53.9% of fatalities and 32.9% of injury crashes occurred at night, leading to multipliers of ≈3.56× (fatalities) and ≈1.47× (injuries).
- NHTSA: 2022 crash statistics
- NHTSA: Time of day and crash involvement
- University of Michigan: Night vs. day crash risk analysis
- Exposure assumption: ~25% of vehicle miles traveled occur at night ([FHWA Lighting Guidance](https://safety.fhwa.dot.gov/roadway_dept/night_visib/lighting_handbook/chap_3/chap3_2.cfm))
Seat-belt Usage (Modifier)
| Seat-belt usage | Fatality risk multiplier | Injury risk multiplier |
|---|---|---|
|
Worn (car) |
1.0 |
1.0 |
|
Not worn (car) |
1.82 |
2.0 |
|
Worn (SUV/van/truck) |
1.0 |
1.0 |
|
Not worn (SUV/van/truck) |
2.5 |
2.857 |
Multipliers reflect NHTSA/IIHS estimates: - In cars, seat belts cut fatality risk by ~45% (→ not wearing = 1 ÷ 0.55 ≈ 1.82×) and serious injury risk by ~50% (→ 2.0×). - In light trucks, belts cut fatality risk ~60% (→ 2.5×) and injury ~65% (→ 2.857×).
RiskModel: Driving/Data:fatality_model
Calculation: fatalities_per_1000_miles * time_fatality_multiplier * belt_fatality_multiplier
Content:
Your estimated fatality risk per 1,000 miles is about {result}.
RiskModel: Driving/Data:injury_model
Calculation: injuries_per_1000_miles * time_injury_multiplier * belt_injury_multiplier
Content:
Your estimated serious injury risk per 1,000 miles is about {result}.
Note on uncertainty: These values are national averages and should be seen as approximate indicators. Actual risks vary depending on geography, roadway type (urban vs. rural), vehicle type, weather conditions, driver demographics, and year-to-year fluctuations. Multipliers for night driving and seat-belt use are based on population-level data and may not precisely predict individual risk.
Generated by ChatGPT-5