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1. So the Ontario government will announce a higher speed limits pilot for 400-series highways.
Interestingly, the Insurance Institute for Highway Safety (IIHS) released a study on this subject one month ago.
(Cc: @JeffYurekMPP @fordnation)
Interestingly, the Insurance Institute for Highway Safety (IIHS) released a study on this subject one month ago.
(Cc: @JeffYurekMPP @fordnation)
2. The United States once had a National Maximum Speed Limit (NMSL) of 55 mph, repealed by Congress in 1995. The study looked at the subsequent effects of higher limits on fatality rates over the 25-year period from 1993-2017.
3. The study also controlled for factors such as % of driving age population under 25, seat belt use, and unemployment rate. 
4. The topline findings:
- 5 mph increase in speed limit associated with an 8.5% increase in fatality rates on highways
- Over the study period, an estimated 36,760 more fatalities than if limits had not increased
- 5 mph increase in speed limit associated with an 8.5% increase in fatality rates on highways
- Over the study period, an estimated 36,760 more fatalities than if limits had not increased
5. This chart tells a story:
6. and this succinctly frames the cost/benefit calculus:
“For the 25 years combined, the conclusion is that 36,760 deaths—or 3.8% of the total—would not have occurred otherwise. That is the size of the trade-off between efficiency/convenience and safety.”
“For the 25 years combined, the conclusion is that 36,760 deaths—or 3.8% of the total—would not have occurred otherwise. That is the size of the trade-off between efficiency/convenience and safety.”
7. To put this in km/h:
The Benefit. If you were to drive 50 km on a formerly 100 km/h highway, 10 km/h faster, you would save 2.7 minutes.
The Cost. if the US figures held, that 10 km/h increase in speed limit might be expected to be associated with 10% increase in fatalities.
The Benefit. If you were to drive 50 km on a formerly 100 km/h highway, 10 km/h faster, you would save 2.7 minutes.
The Cost. if the US figures held, that 10 km/h increase in speed limit might be expected to be associated with 10% increase in fatalities.
8. (and if we’re being honest, the functional speed limit of the 400-series highways is already 120 km/h, so the time savings of a 10 km/h increase would be even less)
9. In sum, higher highway speed limits are an example of populist policy where the very real trade-off is minutes – and votes – for lives.
10. The full study can be found here: iihs.org/frontend/iihs/…
