I think we'd go back to many of the factors we've talked about today and the underlying factors with respect to crude oil pricing. Certainly due to geopolitical events in the oil-producing regions of the Middle East, we've seen advances in the price of crude. It's also the beginning of the summer driving season. That's the time for a high demand for gasoline as refiners are starting to build inventories for the driving season.
So it's a combination of factors, all going back to those underlying principles of the price of crude, supply and demand dynamics of retail gasoline, and some increase in taxes in some jurisdictions. All of those factors together were probably behind it, if you look back historically. I look at historical information to try to read what happened, but certainly I think those would have been some of the factors responsible for the price increases we saw earlier this year.
Michael, you may have some additional information.