Depreciation value of a car

[niky]

Is it common to assume a 10% depreciation value for a car. Or are their methods calculation about how a car is worth after years of operation base on its mileage? Your thoughts please. TIA.

For what purpose? If you're looking at it from an insurance or accounting point of view, you can assume 10%.

But for buy and sell purposes, factors such as whether the model is an outgoing one or a new model, existence of a new model, maintenance issues, fuel economy and brand or model desirability affect resale dramatically.