The example I used was the "Pocket Knife Traders Guide" was put out every few years and was not an attempt to catch market swings - it was solely an attempt for people to spot the more valuable variations and see production numbers, etc. Also I think it would be interesting to get some factory "commentary" on patterns and market analysis. Anything electronic would be a full time job of updating prices. And I am not interested in tracking day to day prices, etc. But I have recently seen knives just list as normal knives on sales threads, eBay, etc. that were actually from tiny production runs and most would never know. There is actually little sense in putting a market price on anything made in the last 5 years.