On your Vehicle page right beneath "Recent Activity" and "tips" section there is Share your MPG and it says "View all the badges and stuff you can share" click on that and just copy and paste the codes into your Signature here.
Just done nearly 3000miles in my New CX5 AWD 175 Sport Nav. Mainly rural and motorway. I am now getting 43.5 MPG. This was by the brim and calculate method. The computer was avaeraging 45.5 MPG. It has been consistantly 2MPG too good. This is not bad at all.
Just reading in Consumer Retorts about some testing they did on mileage at different speeds.....