I just started keeping track of my mileage per gallon, something I should have done a long time ago. In the last couple months I've felt like my MPG dropped off significantly, but without any prior readings I can't prove that it is anything more than my imagination or simply different driving conditions.
Anyway, I have two calculations so far:
10/28/05 - 16.23 gallons ($42.00). Got 225.2 miles on that tank. 13.87 MPG
Note: On this fill-up I added a 5.25 oz. bottle of Lucas Fuel Treatment.
11/05/05 - 15.28 gallons ($36.50). Got 252 miles on that tank. 16.49 MPG
As you can see, there was a pretty big jump from the first fill-up to the second. You can draw your own conclusions on that fuel treatment, but other than that my driving conditions were about as consistant as they can be. Even though I don't feel like I am an aggresive driver with a lead foot, I have still been making a conscious effort to make sure I'm not giving it too much gas from stop lights, etc.