Thanks to Lemons for extensive sales:

https://backpack.tf/item/743008486 https://backpack.tf/profiles/76561198810351708#!/compare/1627948800/1628035200

https://gladiator.tf/listings/6109ebc5f1f4aaafe1190521 5.44 sale ~1 month ago

https://backpack.tf/profiles/76561198165488931#!/compare/1627516800/1628640000

https://backpack.tf/profiles/76561198886167680#!/compare/1627603200/1628380800 - Untrace

The 5.44 sale was listed for a while at 5.66 also

https://gladiator.tf/listings/60fb09d3d7dd7d7776c2646f - 23rd Jul

https://gladiator.tf/listings/6109ab63ff84e154e51427a1 - 3rd Aug

Then changed to 5.44 - https://gladiator.tf/listings/610f1b26cbe2034715ad0699 - 8th Aug

Listed for a while - https://gladiator.tf/listings/611cbe6ca6db39629f3a33c4 - 18th Aug

Given 5.44 took so long to sell and was previously unsold at 5.66 for a while, I would call the cash sales the outliers here

Said cash sales: https://marketplace.tf/items/tf2/602;6;uncraftable

(0.59/1.81)*60=~19.55ref

(0.59/1.81)*60=~19.55ref

(0.59/1.81)*60=~19.55ref

Taking 5.44 given Lemons' suggestions.