Outdated.

http://www.tf2outpost.com/trade/19688083 selling for keys, sold for pure.

http://backpack.tf/profiles/76561198060846575?time=1399532400

http://backpack.tf/profiles/76561198060846575?time=1399791600

Paid approx 3.1 pure, 2 buds and 19 keys. Seems like a high outlier, pre misc nerf?

http://www.tf2outpost.com/trade/18837221

http://backpack.tf/profiles/76561197986966739?time=1396940400

http://backpack.tf/profiles/76561197986966739?time=1397026800

Sold along with a terrorwatt pomp and a C9 rifleman for a burning shako

2.1+3+x = 4.5 x= -0.6 ???

http://backpack.tf/profiles/76561198060846575?time=1399186800

http://backpack.tf/profiles/76561198060846575?time=1399359600

Sold for miami nights enginner cap, 1.9 buds with overpay makes 1.7 buds.

http://www.tf2outpost.com/trade/19610401 b/o 2.5 buds, nearly a month.

http://www.tf2outpost.com/trade/19857930 b/o 55 keys, nearly 2 weeks.

Only recent sales I could find.