Resuggestion, thanks to FishCrimes & K1ng for pointing out my mistake!

Sale 1:

https://backpack.tf/profiles/76561198025486280#!/compare/1532995200/1533772800

https://backpack.tf/profiles/76561198001581441#!/compare/1519344000/1535328000

Sold for 12 keys

Sale 2:

https://backpack.tf/profiles/76561198067837301#!/compare/1533686400/1534118400

https://backpack.tf/profiles/76561198085781776#!/compare/1533254400/1534291200

Untrace.

Sale 3:

https://backpack.tf/profiles/76561198068701324#!/compare/1534204800/1534291200

https://backpack.tf/profiles/76561198137106459#!/compare/1534118400/1534204800

Untrace.

Sale 4:

https://backpack.tf/profiles/76561198137106459#!/compare/1534204800/1534377600

https://backpack.tf/profiles/76561198114402400#!/compare/1534291200/1534377600

Sold for ST Breakdance(8.5)

Sale 5:

https://backpack.tf/profiles/76561198045937306#!/compare/1534032000/1534118400

https://backpack.tf/profiles/76561198130278525#!/compare/1524787200/1535760000

Untrace.

Sale 6 & 7:

https://marketplace.tf/items/30958;5;u36

Sold for 15 & 19 USD

Keys at 1.88, 1.88 USD

Total is 7.98, 10.11 keys

Total sales @:

7.98, 8.5, 10.11, 12 keys

Unsold for 10 for a month.

Buyers up to 7.37 keys, calling 12 the outlier

K1ng's Part:

The sale at 8 isn't really an outlier. 8-10 should work.