I have noticed an increase in depreciation rates over the last 5 or 6 models. More recent models depreciate at a faster rate than older ones at the same stage in their life. I wonder if this is just a natural consequence of higher prices and market saturation. The upper tier version like Pro or Pro Max appear to have slightly lower depreciation rates than the base models, probably because of their more "professional" designation. Surprisingly, Pro and Pro Max make up the bulk of the latest production, which I find surprising.