I would think that along with all other grade inflation, 50 years is a good rule of thumb. I see ’60s Corvettes and Thunderbirds being driven around with Antique plates.  At least, that’s the status the Commonwealth of Massachusetts makes available to the folks who have enough excess cash to engage in the car fancy.

Another rule of thumb.  When it’s no longer useful it’s a collectible (and easily confused with trash).  When the big money finds it, it’s an antique.

Best,

Hendrik 

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