I believe the rule is the previous sales will not count if a drastic change in the market has occurred (which is quite obvious). Being conservative here.

Classifieds - http://backpack.tf/classifieds/?item=Winger&quality=11&tradable=1&craftable=1

1x 2.88

14x 3.00

1x 3.33

1x 3.55

1x 3.66

19x 4.00

1x 4.22

3x 4.33

Selling for 3.00

http://www.tf2outpost.com/trade/25153868 - Young

http://www.tf2outpost.com/trade/25155291 - Young x5

http://www.tf2outpost.com/trade/25156111 - Young

http://www.tf2outpost.com/trade/25153433 - Young (3.33)

http://www.tf2outpost.com/trade/25113747 - 3 days SOLD x1

http://www.tf2outpost.com/trade/25113447 - SOLD (after 2 days)

Selling for 4.00

http://www.tf2outpost.com/trade/25152271 - Young

http://www.tf2outpost.com/trade/25153773 - Young

http://www.tf2outpost.com/trade/25154841 - Young

http://www.tf2outpost.com/trade/25155787 - Young (3.88)

http://www.tf2outpost.com/trade/25147929 - Young x2

http://www.tf2outpost.com/trade/25153708 - Young (3.66)

http://www.tf2outpost.com/trade/25154125 - Young

http://www.tf2outpost.com/trade/25153206 - Young

http://www.tf2outpost.com/trade/25115787 - 3 days

http://www.tf2outpost.com/trade/25152476 - Young

http://www.tf2outpost.com/trade/25146850 - Young

http://www.tf2outpost.com/trade/25121784 - 2 days

http://www.tf2outpost.com/trade/25128117 - 2 days

http://www.tf2outpost.com/trade/25130436 - 1 day

http://www.tf2outpost.com/trade/25141634 - 1 day

http://www.tf2outpost.com/trade/25124492 - 2 days

http://www.tf2outpost.com/trade/25142298 - 1 day

http://www.tf2outpost.com/trade/25139716 - 1 day

Selling for 4.33

http://www.tf2outpost.com/trade/25145109 - 1 day x2