Eight Years of Mileage Tracking and Pretty Charts

I have logged every tank for the last eight years (check signature). Every once and a while I decide to look at the data in different ways. Today I decided to check my average per-tank mileage based on the average temperature during that tank. A note about average temp: I take the high and low temps of each day and average them all together to get the average temp for the tank. It's not scientific but neither am I. I drive to work when it's very cold and I drive home when it's very warm. For my record keeping, I'm close enough.

I created the first tab (located in the bottom-left) by taking all the tanks, sorting them by temperature and charting where the tank mileage fell. But I noticed that some years were better/worse than others and that made for a jagged line.
So I created the second chart in which I broke out the individual years. That one shows each year separately and tells me that 2008 was my best year on record.

Anyway, here are a couple charts showing my per-tank mileage charted against the average temperature during that tank: https://dl.dropbox.com/u/5209940/MileageLog/MileageAtTemperature.htm

Enjoy!

 

uart, I normally turn on the heat when the morning temp is lower than freezing. The A/C normally comes on when it's very hot and very humid. In both cases, it's usually the lowest fan setting. For heat, it's set to 65˚; for A/C, it's set to 85˚.

About the reduced mileage after the dealer trip, Braddles.au posted something for me to check just today.
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