MPG forecasting???

HI all..

Im trying to create a spreadsheet where the user can log how many liters of fuel was consumed per KM ad so on.. so fhar that part is no problem and i can obtain KM per Liter...

However i would also like to see or add an estimated Km per liter column...

so another way of looking at this is
Vehicle "A" consumed X amount of liters from point A to point B considering that X amount of liters was added before the trip..
GREAT
BUT... how much fuel was estimated to be consumed for that trip?

the only thing i can think of is just slowly gather an average of past trips and use that as the estimated Km per liter?

Any suggestion is appreciated.

Thanx in advance.

.
I believe you are on the right track.

Even the newer automobile's that provide such information slowly gather that information based on how much gas is being consumed and the miles driven since
a particular point in time.

Just like the automobile's built-in computer chip, the more information you input into your workbook, the more accurate your program will become.