The overhead console is pretty accurate if you reset it every time that you fill up. If not, you get a total average from when it was last reset until now.
Most I have seen, especially Lincoln's are very accurate. My 08 Ram is within .1mpg of doing it with miles divided by gallons.

 

Thanks guys for the input. I figured the actual mpg was pretty much normal. I do not reset the overhead console everytime I fuel up.

 

City/Hwy mix I average 13.17mpg