Taking sales from Oct 10 on.

sale 1:

https://backpack.tf/profiles/76561197962066085#!/compare/1570579200/1570665600

https://backpack.tf/profiles/76561197994697258#!/compare/1570579200/1570665600

not unusual

Sale 2:

https://backpack.tf/profiles/76561198298597700#!/compare/1574121600/1574208000

https://backpack.tf/profiles/76561198150347450#!/compare/1574121600/1574208000

some kinda bulk

sale 3:

https://backpack.tf/profiles/76561198124114740#!/compare/1570838400/1571184000

https://backpack.tf/profiles/76561198095236132#!/compare/1570838400/1570924800

https://backpack.tf/profiles/76561197960788095#!/compare/1570838400/1570924800

SCM or not unusual till last compare

Sale 4:

https://backpack.tf/profiles/76561197960788095#!/compare/1574467200/1574553600

https://backpack.tf/profiles/76561198011695067#!/compare/1574380800/1574553600

Bulk

Sale 5:

https://backpack.tf/item/6478510323

https://backpack.tf/profiles/76561198053987078#!/compare/1570752000/1571702400

not unusual before this

sale 6:

https://backpack.tf/profiles/76561198159995555#!/compare/1571529600/1571616000

https://backpack.tf/profiles/76561198154211785#!/compare/1571529600/1571616000

not unusual

Sale 7:

https://backpack.tf/profiles/76561198152293052#!/compare/1573862400/1574035200

https://backpack.tf/profiles/76561198307761034#!/compare/1573862400/1573948800

Bulk

sale 8:

https://backpack.tf/profiles/76561198307761034#!/compare/1573862400/1573948800

https://backpack.tf/profiles/76561198802991149#!/compare/1573862400/1573948800

Sold for 6 keys

sale 9:

https://backpack.tf/profiles/76561198027378787#!/compare/1570060800/1570752000

https://backpack.tf/profiles/76561198023051867#!/compare/1570665600/1570752000

Untrace / made unusual

Sale 10:

https://backpack.tf/profiles/76561198023051867#!/compare/1570752000/1570838400

https://backpack.tf/profiles/76561197964546925#!/compare/1570752000/1570838400

SCM

Sale 11:

https://backpack.tf/profiles/76561197961976244#!/compare/1570838400/1571011200

https://backpack.tf/profiles/76561198369769961#!/compare/1560038400/1573948800

Untrace

sale 12:

https://backpack.tf/profiles/76561198369769961#!/compare/1573948800/1574380800

https://backpack.tf/profiles/76561198363395191#!/compare/1573862400/1573948800

QS

Sale 13:

https://backpack.tf/profiles/76561198363395191#!/compare/1573948800/1574035200

https://backpack.tf/profiles/76561198021566555#!/compare/1573862400/1574294400

Untrace

Sale 14:

https://backpack.tf/profiles/76561197962066085#!/compare/1571443200/1571529600

https://backpack.tf/profiles/76561198081907770#!/compare/1572048000/1572134400

not unusual / SCM

Sale 15:

https://backpack.tf/profiles/76561198118150950#!/compare/1571961600/1572048000

https://backpack.tf/profiles/76561197994697258#!/compare/1571961600/1572048000

Bulk

Sale 16:

https://backpack.tf/profiles/76561198074625962#!/compare/1571184000/1571270400

https://backpack.tf/profiles/76561197968968337#!/compare/1571184000/1571270400

Bulk sale

Sale 17:

https://backpack.tf/profiles/76561198329433413#!/compare/1571356800/1571443200

https://backpack.tf/profiles/76561198836967499#!/compare/1571702400/1571875200

Not unusual

Sale 18:

https://backpack.tf/profiles/76561198836967499#!/compare/1572220800/1572393600

https://backpack.tf/profiles/76561198055562931#!/compare/1571961600/1572393600

Untrace

sale 19, 20:

https://marketplace.tf/items/tf2/30921;5;u3027

$34.99 / $1.81 = 19.33 keys <--- https://backpack.tf/item/6680456364

$14 / $1.78 = 7.87 keys

Total sales @:

6, 8, 19 keys

Taking 6 - 8 keys