Why is it that this site still lists Kraken Club's average price at 80,000,000 when it hasn't been that way in ages?
Because its not avg price. Its clearly stated it's Median.
Median is number in middle of the group of ordered numbers.
In group 1,2,3,4,100 Median is 3, while average is 22.
If you look on some servers when you can see whole list of sold KC (like Cerberus) you can easily see that it takes middle number after ordering numbers from lowest to highest. If there is no middle number, because the amount of numbers is even, then it takes avg of 2 middle numbers. For example on Titan there is ten KC prices in history.
Ordered from lowest we have:
10
10
10
10
10
37,458
884,967
25,000,000
41,000,000
50,000,000
So it takes 2 middle prices 10 and 37,458 and takes avg from them (10+37,458) / 2 = 18,734
Obviously presenting Median from several year of sold KCs has very low informative value for someone looking for its present price, but that is whole other story :P