MP sales:

https://marketplace.tf/items/tf2/30844;5;u3030

Jan 12: 9 / 1.78 = 5

Jan 16: 8 / 1.78 = 4.5

Jan 17: 8 / 1.77 = 4.5

Jan 23: 5.95 Not taking as around buy orders

Jan 29: 5.05 Below buy orders

Feb 2: 8 / 1.78 = 4.5

Feb 9: 6.4 / 1.78 = Too close to buy orders

Feb 15: 8.29 / 1.77 = 4.7 https://backpack.tf/item/6263302266

Feb 21: 8.37 / 1.76 = 4.8 https://backpack.tf/item/6645255358

March 1: 5.7 below buy orders

March 13: 7.47 / 1.72 = 4.3

March 17: 7.55 / 1.69 = 4.5 https://backpack.tf/item/7677814053

Bot.tf sale:

https://bot.tf/stats/item?def=30844&q=5&ef=Nether+Void&craft=1&aus=0&ks=0

1 @ 5 keys 13/02/2020

Other trades:

1. https://backpack.tf/item/8199753307

https://backpack.tf/profiles/76561198150072904#!/compare/1581206400/1582156800

Bulk

2. https://backpack.tf/item/8199753307

https://backpack.tf/profiles/76561198081925059#!/compare/1581552000/1581638400

Unusable

3. https://backpack.tf/item/8161550286

https://backpack.tf/profiles/76561198127096855#!/compare/1581206400/1581465600

SCM

4. https://backpack.tf/item/7677814053

https://backpack.tf/profiles/76561198065957709#!/compare/1582934400/1583625600

Sold for 3 keys and 10 ref. Lower than buy orders.

5. https://backpack.tf/item/7449289634

https://backpack.tf/profiles/76561198057550162#!/compare/1583712000/1584748800

Bulk

6. https://backpack.tf/item/7449289634

https://backpack.tf/profiles/76561198302382325#!/compare/1584662400/1584748800

Unusable

7. https://backpack.tf/item/6427402618

https://backpack.tf/profiles/76561198149240383#!/compare/1579132800/1579392000

Unusable

8. https://backpack.tf/item/6427402618

https://backpack.tf/profiles/76561198177872379#!/compare/1580515200/1580601600

Unusable

9. https://backpack.tf/item/6427402618

https://backpack.tf/profiles/76561198337953212#!/compare/1580947200/1581033600

Sold for 4 keys 2 ref

10. https://backpack.tf/item/6427402618

https://backpack.tf/profiles/76561198431725617#!/compare/1581724800/1581811200

Unusable

11. https://backpack.tf/item/6255097944

https://backpack.tf/profiles/76561197963031728#!/compare/1581465600/1581552000

Unusable

12. https://backpack.tf/item/6255097944

https://backpack.tf/profiles/76561197968633696#!/compare/1580342400/1580428800

Unusable

13. https://backpack.tf/item/6255097944

https://backpack.tf/profiles/76561198161953994#!/compare/1579478400/1580688000

Unusable

Taking 4 - 5 as range.