Our gas prices seem to have a weekly cycle between 79.9 and 64.9 per litre. (A litre is close to a quart). The gas stations have a little graph showing how the gas price is divided up, with profit getting 2%. I now wonder where the 20%+ price swing comes out of? It's not the government adjusting the tax rates every day! They've also become cagy, no longer raising prices before the weekend (especially the long weekend), but it does go up on Tuesday or Wednesday or sometimes Monday -- you have to gamble whether the low will be Tuesday morning or fall more for Wednesday.