Seller @1.06 keys Buyers @44.11 ref(.78 keys)

No Glad

https://gladiator.tf/sales?item=Mann+Co.+Supply+Crate+%2318

MP

https://marketplace.tf/items/tf2/5022;6;c18

https://marketplace.tf/items/tf2/5021;6

5/11 2.99/1.98=1.51

SCM

https://steamcommunity.com/market/listings/440/Mann%20Co.%20Supply%20Crate%20Series%20%2318

https://steamcommunity.com/market/listings/440/Mann%20Co.%20Supply%20Crate%20Key

https://imgur.com/a/rm0L4j6

Using hourly key prices

Maxima

5/23 2p 3.04/2.39=1.27

5/19 3p 2.50/2.41=1.04

5/17 7p 2.49/2.39=1.05

5/7 12p 2.27/2.38=.95

5/3 11p 2.36/2.50=.94

4/26 3p 2.41/2.50=.96

Minima

5/22 8a 1.84/2.37=.78

5/17 12p 1.80/2.41=.75

5/11 9a 1.34/2.41=.55

5/10 5a 1.02/2.39=.43

5/4 1p 1.35/2.44=.55

4/30 10a 1.51/2.50=.60

4/27 8p 1.15/2.53=.45

Other Notable Points:

5/23 12p 2.84/2.40=1.18 200x sold

There have been 2 total sales below the .55 minima's, using that as bottom end. Ignoring singular high mp outlier of 1.51. Taking .55-1.25. Note the 200+ sales @1.18 keys yesterday, I'd understand taking .55-1.20 as range because of that.