Man what is this

Sales 1,2,3: $19.99, $17.19, $17.19 on marketplace https://marketplace.tf/items/tf2/31080;5;u162

19.99/1.81 = 11.04 (rounds to 11k),, 2x 17.19/1.87 = 9.12 (rounds to 9k)

Sales 4,5: $15.66 and $16.95 on mannco https://mannco.store/item/440-gourdian-angel-unusual-convict-cap

15.66/1.65 = 9.49 (rounds to 9k), 16.95/ 1.68 = 10.09 (rounds to 10k)

https://backpack.tf/item/9289891758

Sale 6: 8 keys 10 ref

Buyer: https://backpack.tf/profiles/76561198050056686#!/compare/1634688000/1634774400

Seller: https://backpack.tf/profiles/76561199102199351#!/compare/1634688000/1634774400

https://backpack.tf/item/9346762242

Sale 7: Untrace

Buyer: https://backpack.tf/profiles/76561198042405022#!/compare/1635120000/1635206400

Seller: https://backpack.tf/profiles/76561199110809353#!/compare/1635120000/1635206400

Sale 8: Untrace / bulk

Buyer: https://backpack.tf/profiles/76561199084784906#!/compare/1634860800/1634947200

Seller: https://backpack.tf/profiles/76561198053697018#!/compare/1634860800/1634947200

Rest of the history is mp/mannco sales covered above.

Sales at 8, 9, 9, 9, 10, 11. Current seller at 9 and multiple mp listings at 9, so clearly price has changed since the 11k mp sale.

Excluding the sales more than 2 months old (mp 11k sale, mannco 9k sale) and taking 9-10.