Proof below. 6 month-old price.

Sales:

http://www.tf2outpost.com/trade/15767598

-wanted 2.5 buds

-beret+1 key sold for nnb exe=~1.9 buds

http://www.tf2outpost.com/trade/15687803

-wanted 3 buds

-beret+7 keys sold/bought for disco mullet: http://www.tf2outpost.com/trade/15651114

http://backpack.tf/id/76561198107518076?time=1384243200 disco mullet+2 keys

http://backpack.tf/id/76561198107518076?time=1384329600 beret+9 keys

-~2 buds

http://www.tf2outpost.com/trade/15339143

-b/o of 3 buds

-seems to have sold for this pink max: http://www.tf2outpost.com/trade/15441868

-2.4 buds then

http://www.tf2outpost.com/trade/14235385

-wanted 3 buds

-beret+10 keys bought pe l'inspecteur

http://backpack.tf/id/76561198101270322?time=1378969200 cauldron beret+10 keys

http://backpack.tf/id/76561198101270322?time=1379142000 pe l'inspecteur

-2 buds

http://www.tf2outpost.com/trade/13812772

-sold fast for 2 buds like he wanted but 2 buds doesn't look like a quicksell from other trades

http://www.tf2outpost.com/trade/15997687

-wanted ~2.5 buds

-sold for stormy bubble+smoking beret=2.5 buds, a few minutes ago

Current trades:

http://www.tf2outpost.com/trade/16156426

-wants 3 buds, just bought it

Sales: 1.9, 2, 2, 2, 2.4, 2.5

Low end from a sale at 1.9 and high end from a sale at 2.5. Unusual overpay and original prices used.