1 sale

1) Purple Confetti Caribou Companion (22) + 10 keys

https://backpack.tf/profiles/76561198034775190#!/compare/1554163200/1554249600

https://backpack.tf/profiles/76561198423264305#!/compare/1552780800/1554249600

Caribou sold for $39.99 on March 14th, keys were $1.8

https://marketplace.tf/items/30974;5;u7

39.99/1.8 ≈ 22 keys

22 + 10 = 32

------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------

No marketplace sales.

https://marketplace.tf/items/31023;5;u8

------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------

Total: 32

If you will find other sales, you're welcome to report them.

Closing. Need to wait for more sales, guess this is an outlier (32) since buyer for any effect for ~30 keys.