I've also been very interested in true ownership cost of cars, and what I noticed is that for new cars, cost of depreciation overshadows all other costs combine

I've also been very interested in true ownership cost of cars, and what I noticed is that for new cars, cost of depreciation overshadows all other costs combined for the first 2~3 years, longer for luxury brands. So there is no point calculating the TCO of new car over more than 3 years, because if you are OK driving an old car, it's always much cheaper to buy used.