A long time ago I did a calculation on how much the price of a barrel of oil effected the price of gasoline. Great minds think alike, or something like that, and James Hamilton at Econbrowser has come up with a slightly different way to do the calculus.
I did a bottom up number crunch, and he instead looked at how the historical prices correlated:
James Hamilton, Econbrowser, 21 June 2014 (hat tip: NC)
The relation implies that a $10 increase in the price of a barrel of Brent crude oil is typically associated with a 25 cent increase in the average U.S. retail price of a gallon of gasoline
Note, this type of estimate is generally much more accurate than a build it up from the pieces, detailed approach. It will miss major changes in the dynamics of the situation, but most micro-approaches will do that as well.
What I find interesting is that if you put $222/barrel into their calculator, you get a gasoline price of $6.39/gallon. When I did the calculation in 2011, I came up with a price of $6.16/gallon. Given the number of assumptions I had to make, and stated, that seems pretty good to me.