I think that Robin is the only one that can really answer how often and to what degree those values change.

I also think that you are holding on to those values a bit strongly. They really don't mean a damn thing.

Just look at the Boston Pinball Repair site.

http://www.bostonpinball.biz

It's updated every 3 months or so and is a good starting point for historical sold listings.

You can go a step further and average that data with the Pinside data to get an even better picture.

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