In California, they need to include the illegals which would mean counting unlicensed, uninsured and unregistered vehicles, that is a registration not currently active. Same with statistics about drivers. That would mean counting illegals that don't have a driver's license but do drive.
I was rear-ended by a person driving a car with no plates and no documents inside. He ran off. The Highway Patrol stopped but did not take a report. He jokingly asked me if I wanted the car and left. My tow hitch punched the front of the car and left coolant on the ground. I did not take up the cop's offer and just left. None of this will appear on anyone's statistical analysis. I opened the hood and made sure the car could not be started and driven away. Later that day the car was gone. Someone with a tow truck probably has a parts car.