I succeeded in collecting the run of one ounce Kooks commencing with the 1990. Some I bought from dealers and others on eBay. Several months ago I made a list of buying prices from various sources and by a big margin the following years stood out as expensive compared to the average. 1990 1999 2000 2004 2008 European dealers had the 1990 listed at the highest price approx 3 times the average. USA Apmex had the 2008 listed at the highest price but Europeans did not. Any idea why the different years can vary so much in price ? It isn't age because when I did the survey the 1991 was not above the average price. The price doesn't seem to be stongly related to the mintage either. Difficult to find a correlation between market price and year of issue.