Originally Posted by dpazz
....The figures I've stated are averages for each journey not momentary MPG's.
I drive sensibly on the motorway at bang on 70mph as per speedo. Particularly on journeys to work and back - there isn't usually much point in driving aggressively due to traffic etc.
From your comments and the car you drive, you seem to be somewhere on the average. I'd suggest you could look at the 320d combined figure and knock off about 10% for your expected average.
As an example, a 318d driven at motorway speeds (under real world tests) gives about 54mpg. Driven by the average driver, in average conditions, is expected to give around 53mpg. A 520d, from real world tests, 51 motorway and 48mpg total average.
A lot of users on here, reflect heavy driving and/or urban conditions.