The Average Price is an average of the prices paid for an asset, usually over numerous transaction of different amounts and prices.

You calculate Average Price by dividing the total spent on an asset, divided by the total amount of that asset held.

For example, if you purchase $100 of ETH at $150 (0.666 ETH), $100 at $200 (0.5 ETH), and $100 at $250 (0.4 ETH), then you would have spent $300 for 1.566 ETH at an Average Price of $191 ($300 / 1.566).

Average Price is generally used to calculate your average gain or loss, by comparing it to the current price.