You can get the average speed since Trip A or Trip B was reset displayed on the right-hand Multi-Info display. Have a look at the handbook, pages 122, 125, & 133 (page nos. taken from the online handbook for the 2016 model, yours might be slightly different). Can't remember if you can also get this on the "current drive" tab on the big screen, like you can for the MPG, I don't recall seeing it and it's not mentioned in the online manual. So if you want the average for a particular drive, you'll probably have to reset one of the Trips before you set off.