Isn't the air travel statistic flawed?

If there are less aeroplanes than cars, alot less. Doesn't that mean the statistic is biased towards air travel being 'safer'?

no its not because you dont take under consideration how many people can fit on one plane.

The statistics are often stated in terms of passenger-miles, or per 100,000 miles traveled, rather than simple the raw count, which makes it more comparable to other forms of travel.

None the less, in 2007 and 2008, there were no fatalities in commercial aviation (at least in the U.S.), despite the fact that U.S. airlines flew almost 16 billion miles in about 37 million flight hours.

No matter how you want to do the comparison, over those same two years, approximately 80,000 people died in vehicle accidents.

So, which one is safer?