You forgot about the 2 other sales at 9 ref from the classified sell orders.

key http://www.tf2outpost.com/trade/27332133 - This was sold to braven, who ended up selling it to me for 9 ref. Odd.

key http://www.tf2outpost.com/trade/27374417 - Not a sale. Morphine still owns it.

I had the largest WTF moment when I checked one of the key sales and saw that I now own it.

Other 2 sales which I assume were excluded because I forgot to post a screenshot. Both are 9 ref.

http://i.imgur.com/iJb8W4c.png

http://i.imgur.com/9gw6Etu.png

Morphine dropped his price from 1 key to 15 ref.

http://www.tf2outpost.com/trade/27475497

Morphine's sold at 15 ref. Key might be an outlier given the current key price and that the 15 ref one on the classifieds still hasn't sold.