A little bit of oil math.
The world uses an approximate 90 million barrels of oil a day.
That's a lot of oil.
But how much is a barrel per se? well a barrel is approximately 159 litres
http://en.wikipedia.org/wiki/Barrel_%28unit%29 The world uses 14,310,000,000 L of oil per day. Well now that's 14 billion litres. But how much gasoline is that?...
well there's 19.3 US Gallons (73 L) of usable gasoline out of a barrel of crude oil. The rest is heavier and lighter hydrocarbons.
http://www.eia.doe.gov/kids/energy.cfm?page=oil_home-basics#How%20used alright, so we don't use all 14 billion L of oil for gasoline, some of it is used for diesel, heating oil, plastics and other "junk".
so that's a more "reasonable" 6,570,000,000 Litres per day.
What percentage of that is my contribution? I average 90 kms of driving a week, my car averages 10 litres per 100 kms throughout the year, in summer it tends to be better and in deep winter it does lousy. so I use 9 litres per week, or 1.28 Litres per day.
That's approximately 1.948249619482496e-10% of that oil per day. Or if you want to look at it a different way 1.5x my share if you consider there's about 7.1-7.2 billion people in the world today.
And I'm a light user. I only average 13 kms of travel per day.
Considering once it's used there's no real way to get more conventional gasoline. Maybe my next car should be a hybrid.