A thing to consider is the average means there are tons of older cars in the mix, but some new ones slowly creeping in. There are lots of cars from the 90s or even 80s driving around where I'm from. Weather can be quite unforgiving for cars here, temperature ranging from -25C(-13F) to +30C(86F) year round. Lots of salt and some types of pavement seem to be exceptionally bad for timing gears[0]. Owning a car is likely the most expensive thing a normal person can do in Finland.