By half, according to this.

It's only 37% worse, when measured by vehicle-km (I say in an optimistic tone, trying to hide my displeasure at the number).

I lived in Germany for a few years. I was too young to drive at the time, but I remember that my parents were impressed by some of the behaviors taught there, and I've always wished that American driver education was less half-assed than it is.

Btw Germany has no speed limit on the highways

On specific, incredibly well maintained highways. I think they also have an age limit for the cars that can use them? I'm less clear on that one, that may have been lost in translation speaking to my Dutch friend.