Market Price uses an Exponentially Weighted Moving Average (EWMA) based on recent completed sales. 

Newer sales count more than older ones, so the price stays responsive to current market movement without overreacting to a single unusual sale. To reduce noise, the calculation starts from the median of recent sales and softens extreme jumps (especially when sales happen close together), while still allowing larger changes when the market has had more time to move.

We exclude certain sales from the calculation, such as:

• sales that have issues reported on them
• sales of unique items listed with pictures and other metadata