What I am saying, is that to provide a comparison figure, you need to first find the 'normal' mileage of that particular car that you drive.
Just because the window sticker says a certain MPG figure, doesn't mean that every Saturn car like yours will get that same mileage. You could have engine problems, or other things wrong that cause your mileage to fluctuate.
By running through a full tank and keeping note of the mileage, you can see what kind of mileage that the car gets without hypermiling, and then compare the results with the ones that you get from a tank using hypermiling.
( So yes, drive longer between fill-ups - the longer the better ( more accurate ) , and skip hypermiling for one or two tanks till you get a good comparision figure )
Good luck !
