Latest data received .
The market average uses every saved price for an item. Newer prices count more. A price from 7 days ago counts half as much as a price from today. A price from 14 days ago counts a quarter. Older prices still count, just a little.
Each look is also weighted by how many were listed at that cheapest price, up to 200. One huge stack cannot set the price by itself. A new look is saved at most once every 30 seconds.
The latest price is only the most recent cheapest listing. It can sit above or below the average when the market has moved.