Sir with all due respect to posters and their respective cars, I have no clue what we are talking about.
I have never averaged the new Civic on long routes but in City (Karachi) the best I ever got was 9km/l in a VTI M/T.
Also owned and driven several 05 Civics, all EXI/VTI, M/T and PROSMATEC, the best I ever achieved was in a manual 05 VTI and that was around 13.5km/l.
The best I have ever achieved in a sedan was in a 1.0L Belta A/T and City IDSI M/T, approx 15 and 15.5km/l respectively.
A Toyota Prius can achieve 17km/l, but it wont be easy even for a Civic Hybird to get that average unless it is June/July or the batteries are full charged and run purely on battery mode.
The European Civic can surely return 17km/l, the 3 door Civic with L13 and a 6 speeder manual can even achieve 19km/l due to its 200kg lighter weight.
The best automotive journalists have ever achieved is 13km/l for Civic and 14km/l for Corolla including Road & Track, AutoCar, MotorTrend and Car and Driver.
Regards