That sounds like good economy with what's on board.
I've just filled up for the 6th time with the following results: 10.13, 9.97, 9.47, 10.44, 10.59 and 9.32. The last was after cruising the M7 Wednesday night at 120Kmhr. That's a mixture of BP ultimate and Shell V-Power. I drive to Nth Ryde twice a week from the upper Blue Mountains and had one trip to Nowra through Kangaroo Valley. Around the mountains the consumption is 10-12. This is the first time I've had an auto so I'm still coming to grips in how to drive without the auto kicking back too much.
I did notice driving the M4 near Kingswood, where the police markings for aerial radar, that the speedo is out by possibly 5%. Though the car has a sticker from TruSpeed verify the speedo passes certification that would have some qualify +/- % value.