It doesn't look like it to people outside of backpack.tf, but you're actually increasing this item's value based on unsold prices. It's a ruling now that the current suggested unusual values are all wrong so what they were last suggested as must be considered instead.

The original suggested price for this hat was 4.5-5.1: http://backpack.tf/stats/337/5/19

Your two sales at 5 buds and $180 (~5.8 w/buds@ $31), so the suggested range is pretty close.