Been checking my fuel consumption lately after putting in some 98, which i hadn't used for a few years, first tank 30-city 70 highway i got 9.9L/100km's as the average for the whole tank.
2nd tank with a trip to Wollongong (lots of hill climbs back to Sydney) with my usual 30/70 commute i got to down to an average of 9.1 for the whole tank.

(i fill up with the same pump every week and do the calculations by my self with a calculator, also worth noting is i fill up every week at just under empty around 400km's on the trip meter so my figures would drop even more if i used the whole tank by reducing more weight)