Now, many PDO incidents go unreported, but, medium does not offer a number for comparison, so, when you see the headline "11 accidents in 1.7m miles" you have no reference to whether this is high or low.
Good find. The text of the DOT website is a little vague, but I think you're right that the 1.45 per 1M number is only from police reports.
Data for GES [General Estimates System] come from a nationally representative
sample of police reported motor vehicle crashes of all types, from minor to fatal.
... Although various sources suggest that about half the motor vehicle crashes in
the country are not reported to the police, the majority of these unreported crashes
involve only minor property damage and no significant personal injury.
I guess that's saying the actual number should be about double, so ~3 per 1M.
I'm also wondering if any private operators of fleets publish stats. For example, does FedEx or UPS publish accident rates? I know those numbers would also be skewed, larger vehicles, more frequent stops, etc. But it could be another data point.
Now, many PDO incidents go unreported, but, medium does not offer a number for comparison, so, when you see the headline "11 accidents in 1.7m miles" you have no reference to whether this is high or low.