This is probably largely a measure of how much the vehicles are driven. RAM makes commercial vehicles like trucks and vans, which are driven long distances by

This is probably largely a measure of how much the vehicles are driven. RAM makes commercial vehicles like trucks and vans, which are driven long distances by drivers on their job, so it ends up near the top of the list even if the accident rate per-mile-driven is low. Old vehicles are more likely to be driven infrequently (e.g: kept in a pensioner's garage), hence brands that no longer exist like Pontiac, Mercury, and Saturn end up near the bottom.