Thanks for the input so far. I see that most people track data with only per-fillup granularity. What about for trips, especially commonly taken trips? I can imagine wanting to compare various routes to get to work, for example. Any suggestions there?

 

I have come to the conclusion that for my daily commute, the shortest route is the most fuel efficient overall (it also happens to be the quickest most of the time). After some testing I realized that even though I can take another route that gives me better mpg on the gauge, since the trip is a couple miles longer, I actually burn more gas. Kinda defeats the purpose in my opinion.

The catch is that the shorter/less gas route also requires a $2.50 toll (one way only) so the trip that burns less gas costs me more. I pay the toll and save the 0.1 gallon or so of gas. Like buying a hybrid in the first place, it's a conscience decision, not an economic one.

 

I don't track short trips, but I generally track everything else mentioed so far. Additionally, I track when the pips on the fuel gauge drop off, trying to find a pattern. Now THAT'S geeky. What's really geeky is that this is all on my PDA phone...

 

I have tracked every car I have owned, and the procedure is the same: Since I get a printed receipt for the fuel purchase, I simply jot down the odometer on the receipt and let other things do the rest of the calculations. At its core, all you need is distance and amount of fuel. I cannot track temperature or time spent driving or how much is highway because those are all too variable within a tank. Besides, I don't want to live my life that way.

I record my data in Metric, which has precluded me from using GreenHybrid's database -- sorry, but I'm not going to painstakingly convert all my measures. I do track on http://spritmonitor.de, but my master records are in my own spreadsheet. I'll demonstrate the spreadsheet method, and hopefully this will be clear and easy to follow. Look at the following sample for reference, then I'll show you how to build it:



Any rudimentary spreadsheet program should suffice. I started this in AppleWorks and later upgraded to Numbers.

Row 14: Headers

Row 15

• Enter a starting date and odometer reading only. The odometer will be used in the following rows

Row 16

• Column A: Date at time of fill-up
• Column B: Odometer at time of fill-up
• Column C: Amount of fuel at time of fill-up
• Column D: Total price of fuel at time of fill-up
• Column E: =D16/C16
• Column F: =D16/G16
• Column G: =B16-B15 (note the reference to the previous row)
• Column H: =C16/G16*100
• Column I: =(G16*0.621371)/(C16*0.219969)
• Column J: =(G16*0.621371)/(C16*0.264172)

Don't get hung up on what I have chosen for measures and calculations. Use your own or Google up some conversion math.

Now, at this point you have one complete row of data. Tweak the cell formats so that dates display properly, currency is recognized, and that numbers appear with as much precision as you want. Once this row is "finished", insert a new row below, copy the old row and paste it in the new row. If your spreadsheet has any common sense, it will automatically adjust the formulas and preserve the formatting. You may want to test the behaviour before moving on. Since the new row is a copy of the old row, change the data in the first four columns to represent your new tank of fuel.

Row 41: This is the summary row. It is another copy of Row 16, but with the following overrides:

• Column A: N/A
• Column B: N/A
• Column C: =SUM(C15:C40)
• Column D: =SUM(D15:D40)
• Column G: =SUM(G15:G40)

Since we're using the SUM() function, the spreadsheet program shouldn't go crazy over empty cells. Keep one or two empty rows between your data entry and summary row. This will leave you room to insert new rows within the range, and the spreadsheet will automatically increase the row range in the summary. In other words, do not insert new rows immediately above the summary row, or the summary formulas will become incorrect.

 

The reason for using the odometer instead of the trip meter is that the odometer doesn't get reset, meaning that you cannot make an erroneous reading because you forgot to do something.

 

I don't keep track of anything! Makes for a more relaxing drive. It is silly to get all worked up about different methods. All methods have inaccuracies.

 

Interesting as I do not track anything myself.

I like my Cars a lot but don't track anything, like yourself.

Still,

Terry

 

I've kept track in the past, in another life.....

Quit when I realized all keeping track did was increase stress.