Explain impression share and related metrics like top of page rate and absolute top of page rate.

• A. Impression share = impressions / eligible impressions; Top of Page Rate = impressions in the top section; Absolute Top Rate = impressions as the very first result.
• B. Impression share = clicks / impressions.
• C. Top of Page Rate measures position distance from the top.
• D. Absolute Top Rate includes impressions on all devices.

Answer: (A)

The main idea is understanding how often your ads show up compared to how often they could show up. Impression share is calculated as impressions divided by eligible impressions, where eligible impressions are every time your ad could have shown given your targeting, status, and budget. This tells you your overall exposure within the audience you could reach.

Top of Page Rate refers to the portion of your impressions that appear in the top section of the search results—the area above the organic results. Absolute Top of Page Rate is the portion of impressions where your ad is the very first result shown above everything else. These metrics together reveal not just how often you’re shown, but where you’re shown on the page, which directly affects visibility and click potential.

If you see a high impression share but a low absolute top rate, your ads are often shown in top positions but not always the very first slot. If your impression share is low, it could indicate limited budget, bidding, or quality issues limiting your exposure.

Impression share differs from click-related metrics (for example, CTR, which is clicks divided by impressions), and Top of Page Rate and Absolute Top of Page Rate are about position on the page, not about distance or device coverage.