I fully expect that over the course of the day there have been many price increases and decreases, depending on where you are in the country.
I've been in this job since November, and I just recently discovered that, for example, in British Columbia the price that you see outside is not necessarily the price that you actually pay when you arrive at the gas station. It's a different marketing reality in Vancouver from what it is in Montreal and in Toronto.
The fact of the matter is that there is an element to this that is local market dynamics, where the number of gas stations on a given corner in fact does matter. Those are decisions taken by individual business people in the context of everything they're selling when you drive into that gas station.