Xli normally shoud do 14 litres/km in city (I am talking about Islamabad, as it depends on traffic congestion and road conditions, too much idling can increaes your fuel consumption per litre, so it will vary form city to city).
Try to find a good petrol pump, as most of the pumps just give your something 0.7 litres or less and not a full litre, so it not really the car in most cases, but less fuel given by pumps which is responsible for low milage.