Hi there,

Hope you guys can help me, I've bent my brain over this simple problem for a couple of hours and for some reason I cannot see the light.

I have data for 2 weeks which tells me the Miles Per Gallon fuel consumption of a car each day. I also know the Volume in Gallons consumed on those days - this then allows me to calculate the distance covered.

How do I work out how more or less fuel economic the second week was compared to the first?

My initial thought is that I simply take the total distance during the first week, divided by the total gallons consumed during that time, and then subtract the same values for the second week. However, is there a "smooth way" I can do this without having to calculate the distance column - IE just use the MPG and/or Gallons inputs?

If you guys could let me know if I'm right in my idea, if there's any shortcut way to remove the need for the Distance column and confirm my result that'd be great. I get 1.77 less MPG in week 2 compare to week 1 - IE a drop of of 1.77 MPG

Thanks guys.