For a while I have been playing with an app in the iPhone called mpgcalc. There are two versions, free and the full one that stores more entries and also gives a wider choice of stats. mpgcalc data The export data file is a txt file but comma separated and it goes into excel pretty easily and here is the resulting graph. It shows 19 entries. The 1st is actually the sum of the fuel put in and the miles ridden from a whole load of entries I would have lost as data isn't transferable if you pay the 69p and upgrade to the pay app. Shows a pretty consistent pattern with a wide difference between the highest and the lowest mpg. This is for the UK gallon. When I fill up tonight the graph is liable to take a dip as I was quite "spirited" on the way home after I was blocked on my favourite curve by a muppet in a BMW 5-series. Outside the Emirates Stadium The ride in this morning was pretty easy. The same holdup as yesterday, so there must ...