Great point N Spec. To expand on this, the car went from $90K new to $57,650 which is a $32,350 reduction in ten years or $3,235 per year. If it is worth $22,543 in 5 more years then they are saying it will depreciate $7,021 per year going forward. Their little circle graph also indicates this as the dark circle (value in 2014) is closer in size to the silver circle (2005) than the light circle (2019) even though it represents half the time. In other words, they are saying that the car is going to depreciate at more than double the rate of depreciation to date. This contradicts the general expectation as described in this wikipedia reference:
http://en.wikipedia.org/wiki/Automobile_costs#Depreciation which shows automobile depreciation to generally be between 15% to 20% year off the car's current value and therefore the overall cost reduction actually
slows over time. Even if we applied the same rate from the past 10 years, the value of the car only drops $16,175 to $41,475 making the NSX the cheaper of the two in terms of cost per mile. Of course none of this takes into account market forces that cause some cars to be collectible. This consideration would only make their anticipated value even more inaccurate.
The good news here is that for those of us who are still looking to pick up another NSX, they may have just saved us a little money. For those of us that already have one, we will have to see if this example of poor journalism has any lasting effect.
One other thought: I believe the article says they got their depreciation values from Black Book which is a paid subscription service so I could't verify that they had the correct reference. If anyone is a dealer or has access to that subscription, it would be interesting to see if they could verify that BB actually had those numbers. I find it hard to believe that a company dedicated to being experts in car values could blow it that badly.