[anentropic]

from the OP link

"the 15 largest ships in the world emit as much nitrogen oxide and sulphur oxide as the world’s 760 million cars"

[bunnymancer]

With 760 million cars in the world and 7 billion people, that's one car per 921 people..

So if you have a car and your family is smaller than 921 children, you're ahead of the game, globally.

[joss82]

9.21 people, actually.

[dcposch]

one car per 9.21 people, not 921