Lotta recent attempts at this. Let's get it right.

SALES:

http://www.tf2outpost.com/trade/21999150 Sold for Lantern Bubble Pipe (8.2) + 1 pure

(8.2 * 0.9) + 1 = 8.38 (rounding to 8.5)

Histories:

http://www.tf2outpost.com/item/440,2875529449,341,5

http://www.tf2outpost.com/item/440,2875529455,597,5

http://backpack.tf/item/92022016

http://www.tf2outpost.com/trade/21391676 Sold for TW Voodoo (7) + PE Spartan (4.7)

11.7 * 0.9 = 10.53 (But seller had B/O of 9. = 9)

Histories;

http://www.tf2outpost.com/item/440,2875529449,341,5

http://www.tf2outpost.com/item/440,2832920154,935,5

http://www.tf2outpost.com/item/440,2832920166,340,5

http://www.tf2outpost.com/trade/19531235 Sold for Harvest Med-Ushanka (6.5)

6.5 * 0.9 = 5.85 (rounding to 5.9 - outlier)

Histories:

http://www.tf2outpost.com/item/440,2866225268,341,5

http://www.tf2outpost.com/item/440,2649172088,778,5

http://www.tf2outpost.com/trade/19548983 Sold for P.Fetti Beak (4.8) + G.Fetti Beak (4.3) + G.Fetti Pickel (1)

10.1 * 0.9 = 9.09 (rounding to 9)

Histories;

http://www.tf2outpost.com/item/440,2596844993,341,5

http://www.tf2outpost.com/trade/19741359

Let it ride.