Not so much a counter as a I-need-this-done-for-a-suggestion-I'm-doing.

OUTPOST OVERVIEW:

http://www.tf2outpost.com/trade/21891780 B/O of 3.4 (6 days)

http://www.tf2outpost.com/trade/21469820 B/O of ~2.8 (3 weeks)

SALES:

http://www.tf2outpost.com/trade/21602906 Sold for Smoking Beak (Outdated at 2.8, mini at 2.35) + BMOC (~0.5 at point of sale)

2.85 * 0.9 = 2.565 (rounding to 2.6)

Histories:

http://www.tf2outpost.com/item/440,2832482731,937,5

http://www.tf2outpost.com/trade/21612457

http://www.tf2outpost.com/trade/21085520 Sold for DBD Trilby (4)

4 * 0.9 = 3.6 - outlier

Histories:

http://www.tf2outpost.com/item/440,2832482731,937,5

http://www.tf2outpost.com/item/440,2762283704,324,5

Beak mini:

http://www.tf2outpost.com/trade/21312831 Sold for Vintage Bills (1.5) + 1 pure + sweets (~0.1)

(1.6 * 0.9) + 1 = 2.44 (rounding to 2.4)

Histories:

http://www.tf2outpost.com/item/440,2828920409,315,5

http://www.tf2outpost.com/item/440,1814853863,126,3

http://www.tf2outpost.com/trade/21123085 Sold for KaW Das Hazmat (2.6)

2.6 * 0.9 = 2.34 (rounding to 2.3)

Histories:

http://www.tf2outpost.com/item/440,2828920409,315,5

http://www.tf2outpost.com/item/440,2782841358,30095,5

Taking 2.3-2.4.

Let it ride.