Rocketman;
Your data base of gun "values" interests me. Assuming these values (let's call them market values) are what individuals were inclined to pay for gun(s) during the data base collection period, is the data contained in an software application that could produce "curves" of the market value of the same gun(s) over the 20 year period?
Bush, My data is not quite that extensive. At least once a year I run a goodly number of the pigeon holes and look for correlation. There haven't been any curves so far. 15 years ago OI saw more outliers on the high side, but not enough to call it a trend. Now, I'm expecting to see more outliers on the low side. Whether there enough guns selling below value to call it a trend is yet to be seen. The "curves" you ask about are actually flat at this time.
Bright question!
DDA
