That is the best way to answer the post: city only, mixed, or hwy driving.
Actually, I think that's totally meaningless. What "city" etc means to one person is something else entirely to another.
The only meaningful comparison is the same route(s) by the same driver, with different vehicles for long periods of time (I'm thinking minimum 20k, up to 50k depending on the type of driving).
And even then, SOMEONE will say "You claim that your mileage went UP in the 5G while mine went down" wah, wah, wah. Chalk that up to non-scientific methodology on the part of one, the other, or both.
The automakers and EPA spend millions doing fuel mileage testing. While very few people will agree they are "spot on", I can guarantee they are a whole lot better at getting a "good" number than a bunch of backyard fuel mileage engineers.