In my case depreciation is zero. The car is a high mileage older BMW. If it's worth anything, it'll be worth just as much or just as little a year from now.
No, for me the biggest cost is gas, then tires, then insurance, then oil/filter changes, and it goes down from there. I drive it 30k a year which helps make for that balance. If I drove much less or used cheap tires, then yes insurance would move up to second place.
Certainly on a newer car depreciation could easily dwarf the fuel cost. One excellent reason to have older cars and keep them a long time, if you can hack doing that. I love these old things, so I'm happy.
Actually, the main reason I did the spreadsheet was to find out the accumulated cost of things like using techron, MMO, expensive vs. cheap oil, BMW vs Zerex coolant, and stuff like that. I did it so I can look at each of those on a cents-per mile, cents per gallon of gas, dollars per month/year, etc, whatever basis. It is very instructive. Including all fluids, additives and the like I only spend ~$300 a year on maintenance, while spending around $2200 on fuel, another $300 on insurance and $480 on tires. So, a few pennies here and there for better fluids or more frequent service intervals, or other stuff to keep it running a long time, is really pretty insubstantial when it comes to the big picture. And I learned that each time I fill up the tank, the $2.20 I pay for each gallon of gas corresponds to around $1.12 in other expenses, or around 50% of the fillup amount at todays gas prices.
- Glenn