I don't know, but I ran my own numbers for my car and ended up with $0.25/mile. I counted:
- insurance cost of second car (liability only)
- depreciation
- gas
- maintenance and estimated repairs
This was for my car, which was ~5 years old when I got it and is very fuel efficient. I found that depreciation makes up more than half of the total cost, so a newer car would likely have more depreciation than an older car. I got mine for $10k, and in 5 years, it's worth $5k. I think that's pretty common, regardless of the age of the car, so a ~$20k car would depreciate to ~$10k in 5 years. Also, newer cars are more expensive to insure, and taking a car to a shop is more expensive than doing it yourself.
So $0.50 sounds reasonable for the average, relatively new car that is taken to the shop for maintenance and repairs.
- insurance cost of second car (liability only) - depreciation - gas - maintenance and estimated repairs
This was for my car, which was ~5 years old when I got it and is very fuel efficient. I found that depreciation makes up more than half of the total cost, so a newer car would likely have more depreciation than an older car. I got mine for $10k, and in 5 years, it's worth $5k. I think that's pretty common, regardless of the age of the car, so a ~$20k car would depreciate to ~$10k in 5 years. Also, newer cars are more expensive to insure, and taking a car to a shop is more expensive than doing it yourself.
So $0.50 sounds reasonable for the average, relatively new car that is taken to the shop for maintenance and repairs.