Maybe you right,2 sales at ~4,2 sales at ~5.5.Probably even 6.6 looks like a outlier(it's more maybe)

First Sale

http://www.tf2outpost.com/trade/24841948 4 buds pure

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Second sale

Before: http://backpack.tf/profiles/76561198007926966?time=1422604800

After: http://backpack.tf/profiles/76561198007926966?time=1422691200

Sold for DBD canon + Pro KS Aussie Force-A-Nature(price with) 4.3*0.9 + 1.7*0.9=5.4 rounding to 5.5

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Price with Kit: http://puu.sh/fM8mz/f3d6a53127.png avg. $55, = ~1.7) (provided by MaGenta)

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Third Sale

Before: http://backpack.tf/profiles/76561198007926966?time=1423209600

After: http://backpack.tf/profiles/76561198007926966?time=1423728000

Sold for Hellfire Lucky Shot + Pro KS Sniper //Glasgow was offered on Lucky Show,no overpay// 5.95-0.35=5.6 rounding to 5.5

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Price with Kit: http://puu.sh/fPcQF/e44d836d09.png avg. ~$8, = 4 keys (provided by MaGenta)

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Fourth Sale

Before: http://backpack.tf/profiles/76561198061219874?time=1423728000

After: http://backpack.tf/profiles/76561198061219874?time=1423814400

Sold for Aussie RL+Blizz Light+sweets/ more than a 6.6,~outlier

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Fifth Sale

http://www.tf2outpost.com/trade/24819074

after calculating ~4.2

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