Average mpg & total fuel used

First off, both of these parameters provide information, just not the information I was hoping to get.  The Average mpg is the total ave. mpg over all the miles driven, same as the total fuel useage is over all the miles driven.

What I was looking for was having a resettable Ave mpg that I could use in between legs of a trip. So, I would have the Trip Ave mpg running and another Ave mpg that I could reset at the beginning of a day's drive. (Similar to the trip meter and distance driven)

I would also like a fuel used indicator that would be resettable via the Fill Up button.  Yes, I could just use the fuel level indicator and do the math in my head but....

Thanks,
Steve