What kind of driving are you doing? Long highway runs or short stop,go trips? How fast are you driving on these trips? Are you estimating these numbers from the Average Consumption on the MFD per trip, or is this an overall tank?
At first glance your mileage does seem a little low, but that depends heavily on the answers to the above questions.
Came with: Sunroof, BT, Dynaudio, Cold Weather pkg, Blue Graphite Metallic, car purchased new 8/10 - approx 65000 miles now
Upgrades: "Euro"switch, Comfort window feature enabled, fog lights as DRL, heated seat memory, 9w7 BT, auto hatch open, side mirror puddle lights, door warning lights, rear footwell lights, DieselGeek shift kit, winter snow tires used (I switch to indirect TPMS), aluminum kickplates, monster mats.