There is a guide on how to deal with scm sales.

With reference to the rules

http://forums.backpack.tf/index.php?/topic/6033-new-unusual-price-suggestion-guide-the-cheat-sheet/

Steam Community Market Sales

For each SCM sale, please provide proof (screenshot) that the hat of that particular effect sold for the said price

To determine a trade value, you should take in consideration BOTH what a buyer paid and what the seller sold (i.e. you will get a range from a single sale. low end = what the seller received; high end = what the buyer paid)

Buyer value: If the hat is >1 buds in value, take the sale value divided by the value of buds AT THE TIME. If the hat is <1 buds in value, take the sale value divided by the value of keys AT THE TIME.

Seller value: First factor in steam tax. Divide the sale value by 1.15. Then divide the result by the value of buds or keys at the time of the sale as appropriate.

Treat SCM sales as you would other sales - compare the sale value to other sales and b/os to determine if it is an outlier)

In this case, here is the calculation . I have done it in pounds since that is my currency. (it is 90.53 pounds from what i can tell from the graph and the date of the sale)

Buds value on the 7th of January : a range of 22.63 pounds - 25.43 pounds. Taking 24.03 pounds as the value of buds.

Buyer value: 90.53 pounds/ 24.03= ~3.8 buds

Seller value: 90.53/1.15 = 78.7. 78.7 / 24.03 = 3.3 buds.

This sale would give a value of 3.3-3.8 buds. I will let you resuggest at this range.