Spreadsheet opened fine for me…
I wouldn't have the patience to prepare a spreadsheet, but I do like reading it
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Your overall average of 21.4 is a bit better than my (DIS) average of 20.6, but that's probably because I don't use mine for commuting
I also use a mix of Tesco Momentum, Shell Nitro, and BP Ultimate (the last of these is hard to get hold of near me tho'), and don't think there's much to choose between them.