What should be used to investigate why a line item isn’t winning the majority of qualifying open auction impressions?

What should be used to investigate why a line item isn’t winning the majority of qualifying open auction impressions?

• A General or Standard report grouped by channel
• The “Line Item Settings” CSV
• The Inventory Marketplace forecast
• The line item’s impressions lost chart

Correct answer is

• The line item’s impressions lost chart

Explanation: The impressions lost chart illustrates, over the past seven days, how many additional impressions that matched your line items’ targeting could have been purchased.

Impressions are lost because your line items’:

• Frequency cap is too low, or
• Budget is too low, or
• Bid is too low

Read more here: https://support.google.com/displayvideo/answer/3721824