Originally Posted by TerminatorX5

I keep track of my mileage by keeping an excel spreadsheet. Here is a snapshot of a few fill-ups, 93 octane, E53 4.8iS, mostly highway miles:

Date ------ mileage -- ppg ------ gal ------ sale --- vendor -- miles driven -- MPG ----- cost per mile
9/25/2012 ----- 75671 -------- $3.929 ---- 21.1 ---------- $82.90 ----- Wawa ------ 357 ----------- 16.91943 -------- $0.23
9/29/2012 ------76003 -------- $3.849 ---- 19.47 -------- $74.94 ----- Wawa ------ 332 -------------17.05187 -------- $0.23
10/4/2012 ----- 76386 -------- $3.819 ---- 22.848 ------- $87.26 ----- Sunoco ---- 383 ------------ 16.76296 -------- $0.23
10/5/2012 ----- 76468 -------- $3.819 ---- 4.393 -------- $16.78 ----- Wawa ------ 82 ------------- 18.66606 -------- $0.20
10/6/2012 ----- 76877--------- $3.819 ------21.947--------$83.82 ------Wawa ------409 -------------18.6358 -------$0.20
10/10/2012 --- 77246 -------- $3.809 ------22.203-------- $84.57 ----- Wawa ------ 369 ----------16.61938 -------$0.23
10/14/2012 ---- 77557 --------$3.809 ------18.36 ---------$69.93------ Wawa --------311 -----------16.939 -------$0.22
10/17/2012 --- 77909 -------- $3.859 ------20.293 --------$78.31 ---- 7-eleven ------ 352 --------17.34588 -------$0.22