Gasoline Experiment, Part 3

That's more like it.  For my latest tank of gas, I got 36.96 miles per gallon using Shell gas instead of the generic grocery store brand.  Just to make sure this is not a fluke, I checked all of my MPGs for as far back as I could go.  This revealed some striking numbers.  I did, indeed, have some previous tanks of gas as high as 35.99 MPG.  However, my records do not indicate where I purchased the gas.  My monthly average MPG, though, indicate 30 MPG during the cold months and 32-33 MPG during the warm months.  Therefore, a monthly average over 33.66 MPG should prove the Shell gas is a causal factor.  I guess this means my next gasoline post will be at the beginning of next month.