30 Days:

https://gyazo.com/8e7dbdd28a18eff506b6d16fe6ac516d

https://bot.tf/stats/item?def=1067&q=1&ef=&craft=1&aus=0&ks=0

Sold:

2 @ 19 keys

1 @ 17 keys, 36.66 ref

https://backpack.tf/profiles/76561198175367966#!/compare/1580947200/1581033600

19 Keys

Bought:

1 @ 16 keys, 1.11 ref

1 @ 16 keys, 28.22 ref

1 @ 16 keys, 33.77 ref

https://backpack.tf/profiles/76561198175367966#!/compare/1579996800/1580083200

17 Keys

Seller: 27 Keys

Buyers: 17.13 Keys(1) | 17.11 Keys

30 Days:

https://marketplace.tf/items/tf2/1067;1

$41 / $1.78 = 23.03 keys

$38.8 / $1.78 = 21.80 keys

$37.99 / $1.78 = 21.34 keys

$35.34 / $1.77 = 19.97 keys

$32.94 / $1.78 = 18.51 keys

$33.27 / $1.79 = 18.59 keys

$33.27 / $1.79 = 18.59 keys

$40 / $1.77 = 22.60 keys

$40 / $1.76 = 22.73 keys

$41 / $1.76 = 23.30 keys

$34.99 / $1.76 = 19.88 keys

$34.99 / $1.78 = 19.66 keys

$40 / $1.78 = 22.47 keys

$37.4 / $1.77 = 21.12 keys

Sellers: $37.40(1) | $37.78(1) | $169(1)

7 Days:

https://steamcommunity.com/market/listings/440/Genuine%20Grandmaster

https://imgur.com/a/wQ1WFaA

$39.76 / $2.42 = 16.42 keys

$36.31 / $2.38 = 15.25 keys

$35.49 / $2.37 = 14.97 keys

$45.39 / $2.38 = 19.07 keys

$43.30 / $2.38 = 18.19 keys

$45.91 / $2.39 = 19.20 keys

Sellers: $45.97(1) | $46(1) | $57.50(1)

Buyers: $36.31(1) | $36.28(1) | $36.06(1)

Usable Sales:

17.7, 18.2, 18.5, 18.6(2), 19(3), 19.05, 19.2

Sales higher than 19.2 keys is countered by SCM seller