I've had the same car for around 2 years now.
I believe what you're getting is about right, if its got the 4 speed automatic box.
You should be able to improve on that via a tune.
You have a denso ecu so its easily tunable.
Depending on the price and availability you could even go for e85 when you get the tune.
I'm currently on a kido tune from Matt. Very worthwhile getting one of his tunes. I ran a bp98 tune for about a year and now I'm on a flex fuel e85 tune.
Other things to consider would be changing your spark plugs if they haven't been done yet. You should find that yours will be at the end of their lifespan.
A good service never hurts.
But basically your fuel consumption seems correct and you won't get a massive improvement in fuel economy unless you start hypermiling