I wonder how you even calculate that? Is a single screw a part? Is the whole engine a part, or made of lots of parts? How far do you break each thing down unti

I wonder how you even calculate that? Is a single screw a part? Is the whole engine a part, or made of lots of parts? How far do you break each thing down until it’s a single part? Is it when it can’t be taken apart without cutting something? Could you get past that rule by just welding the things made by cheap workers together? So they are no longer seperate parts? I have so many questions. You could say 40% vehicle parts by mass but that doesn’t seem to capture the intent well either.