Calculating MPG including Partial Fill-ups

[Hobo_the_Wonder_Dog]

I need a way to calculate MPG even when there are not total fill-ups.  Example: Gas prices are lower in the next state so, I only purchase $25 of fuel to get me to the cheaper fuel.  When I get to the next location and fill-up I do not want to rely on memory or get out of the practice of entering every purchase.  So, can Excel calculate this easily with a formula?

In my spreadsheet I added a box which I can check if it is a partial fill-up.  Does anyone know how or have suggestions or know how to accomplish my need in Excel.  Thank you for your help!

[#2]

@Hobo_the_Wonder_Dog 

Here's a radical suggestion, since you don't want to rely on memory: paper and pencil.

Have a little notebook with you in your car and write down the amount of gas purchased each time, not just when it's "partial." BECAUSE it is in fact a partial fill-up every time, even though it may be quite low. Assuming you want to be anywhere near accurate with your MPG calculations, you need not only to have the miles driven be accurate but also the gallons of gas.

[#3]

Hi @Hobo_the_Wonder_Dog 

In your spreadsheet you'd need a column with last Odometer reading to get your miles then another column with gallons of fuel and even a 3rd with $ spent

I've attached an example of the type of thing you'd need

[#4]

@Hobo_the_Wonder_Dog 

An additional thought: Do you have a mobile device (hard to imagine anyone who doesn't these days)? Especially if you have an iPad or equivalent, it's quite easy to have your Excel software on that device, so you can do data entry on a real-time basis and need neither memory nor paper and pencil records.

[#5]

@Hobo_the_Wonder_Dog ,

@mathetes makes an interesting point,  sometimes we get too caught up in Excel so maybe an App like MPG Calc Free or Gas Manager can do what you want much better more easily.

[#6]

@Hobo_the_Wonder_Dog 

Actually, Hobo, with your mobile device--most likely either an iOS or an Android system--you have immediate access to Numbers* or Google Sheets*, either one of which (though neither is up to all of Excel's capabilities) is fully capable of tracking and calculating MPG. You can have all the satisfaction of creating your own app.

I have a little spreadsheet in Numbers, for example, that I can use to keep score in Scrabble (so I don't need to use outmoded technology like paper and pencil).....

*I trust it's not a violation of microsoft's techcommunity rules to utter the names of these competitors. :)