Then just note the vehicle volume and don't divide your deaths by volume? When you divide your deaths by volume you're implying that there's some value in a met

Then just note the vehicle volume and don't divide your deaths by volume? When you divide your deaths by volume you're implying that there's some value in a metric that amortizes deaths by vehicle volumes. Automobile volume is just one of several variables and simplifying this equation is why the US has a much higher traffic crash and fatality rate than any other developed country in the world.