Wow 3 years since the last update.

Sales

Sale 1: Untrace, maybe upgrade

https://backpack.tf/profiles/76561198057414229#!/compare/1597708800/1597881600

https://backpack.tf/profiles/76561198021801815#!/compare/1577318400/1599350400

Sale 2: Sold for 16 keys

https://backpack.tf/profiles/76561198002757046#!/compare/1597449600/1597536000

https://backpack.tf/profiles/76561198057414229#!/compare/1596326400/1597708800

Sale 3: Untrace

https://backpack.tf/profiles/76561199008748726#!/compare/1596931200/1597190400

https://backpack.tf/profiles/76561198002757046#!/compare/1596844800/1596931200

Sale 4: Sold for 18 keys

https://backpack.tf/profiles/76561198928421771#!/compare/1596412800/1596499200

https://backpack.tf/profiles/76561199008748726#!/compare/1594425600/1596758400

https://bot.tf/stats/item?def=105&q=5&ef=Circling%20Peace%20Sign&craft=1&aus=0&ks=0&source=browser_script

https://gyazo.com/50736eee789e3db9518c5d9d38f0d3b6

Sale 5: Sold for 16 keys

https://backpack.tf/profiles/76561198985910282#!/compare/1596326400/1596412800

https://backpack.tf/profiles/76561198121096016#!/compare/1596240000/1596412800

https://bot.tf/stats/item?def=105&q=5&ef=Circling%20Peace%20Sign&craft=1&aus=0&ks=0&source=browser_script

https://gyazo.com/50736eee789e3db9518c5d9d38f0d3b6

Sale 6: Sold for 14 keys~

https://backpack.tf/profiles/76561198002757046#!/compare/1594771200/1595462400

https://backpack.tf/profiles/76561198985910282#!/compare/1595376000/1595548800

https://bot.tf/stats/item?def=105&q=5&ef=Circling%20Peace%20Sign&craft=1&aus=0&ks=0&source=browser_script

https://gyazo.com/50736eee789e3db9518c5d9d38f0d3b6

Sale 7: Untrace

https://backpack.tf/profiles/76561198801841170#!/compare/1594080000/1599609600

https://backpack.tf/profiles/76561198002757046#!/compare/1593993600/1594080000

Marketplace

https://marketplace.tf/items/tf2/105;5;u18

September

$34 on September 7 (34/1.83 = 19~)

https://manic.tf/keyprice/?at=2020-09-07

Classifieds

https://gyazo.com/41f3a54272f1c97ab3409a5373d69c38

Summary

Sales at 14, 16, 16, and 18.

Marketplace sales at 19.

Conclusion

14 went to a buyorder, excluding as it's very close to buyers.

Going with 16-19 here.