I own a celerio manual LXI and I am very happy about it. I am getting mileage of 16+ kmpl in the Bangalore city traffic(Indiranagar to KR puram) with 100% AC on. Highway I am getting 22+(70 to 80 kmph speed) with 100% ac on.
I am following all the decent driving tips and filling petrol near to manipal hospital HP petrol bunk old airport road.Since petrol bunks are more important for FE.Dot see the petrol meter bar and calculate, if so you will end up with frustration
Fill the tank full 35 litters, just tell the bunk guys to fill the tank full cut off. The pump will cut off automatically if the tank is full. After filling the tank reset your distance meter to zero(A or B) Drive the car in regular style for another 40 kms or plus. After this again go to the same bunk and full tank tank for full cutoff. Note down the litters need to full the tank. For example if it 2 litter and 40 km done then you are getting 20kmpl.
The above method is accurate one. 16+ kmpl in city for petrol is very excellent.