Very hard to tell you. It depends on many factor. (peak hour, traffic lights, slope, road bump,speed). A will tell you his urban FC is 12+km/l while B is only 10+km/l but both are valid as B every morning need to pass 6 traffic light and climb up some slope while A only pass 2 traffic light, no school on the way to his work place and generally living in flat area.

You can come here to do your own research:
http://blmclub.proboards.com/index.cgi?boa...read=319&page=1

http://www.oneshift.com/pdb/lcmuserfc.php?...%3D31%26aso%3D0

http://www.motortrader.com.my/asp/forum/to...?TOPIC_ID=26810

Some guideline to save fuel
http://www.fueleconomy.gov/feg/driveHabits.shtml

http://kereta.info/proton-new-saga-blm-fue...ult-44-kmlitre/

http://www.hypermiling.com/index.html

http://www.fuel-economy.co.uk/toptips.shtml

http://www.sgcarmart.com/news/writeup.php?AID=85&PN=1