This frequently comes up, we even have a FAQ about it:
Why don't you list everything in order of best fuel economy?
We don't want to provide any incentive for putting in false data so we don't have leader boards. And we don't yet have enough participation to make averages tamper-proof, except perhaps in the case of the Jetta where we have high participation numbers.
I think we might be able to do top 10 lists someday if we have enough people reporting, but I don't think we're there yet.
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