1.6 Manual eating through Fuel

[bristoldub]

I have a 1.6 Passat SE business, on a 65 plate with about 9k miles.

Have a concern over the mileage return I am getting on a full tank of Diesel, sits around 450 MAX in total with the first quarter of a tank generally gone in about 100-120 miles, motorway or city driving. Colleague has the 2Ltr which I know has a larger tank but raves about the fuel consumption and I’m not seeing it. Just wondered what I should be expecting to get out of a tank or am I doing ok with 450 MAX??!?