Impression share, Auction Insights, benchmark CTR and CPC, and how to use competitive data to diagnose Shopping campaign performance — not just monitor it.
Competitive metrics in Shopping give you a window into how your campaigns stack up against other advertisers bidding on the same products and queries. I use these metrics every month in client reviews — not just to report what happened, but to diagnose why. If impression share drops while benchmark CPC stays flat, that tells a different story than if impression share drops while benchmark CPC spikes. The exam tests these metrics because they require interpretation, not just definition. Here's what you need to know.
Correct answer: B. The percentage of total eligible impressions your Shopping ads actually received, out of the total impressions they were eligible for based on targeting, feed quality, and bids
Impression share tells you what percentage of the available Shopping auction you're actually winning. A 40% impression share means your ads showed in 40% of auctions where they were eligible — and the remaining 60% went to competitors or were lost due to budget or rank. I treat impression share as a health check: if it's dropping without any changes to your campaign, it signals either increased competition, a feed quality issue, or a budget constraint that's limiting serving. Each cause has a different fix.
Correct answer: B. Lost due to budget (the campaign ran out of daily budget before capturing all eligible impressions) and lost due to rank (bids or feed quality were insufficient to win the auction)
These two loss reasons point to completely different solutions. If impression share lost to budget is high, the campaign needs more budget — it's literally running out of money before the day ends. If impression share lost to rank is high, the fix is either higher bids or better feed quality (since Shopping rank considers both bid and product data quality). I look at both metrics together: a campaign losing 30% to budget and 20% to rank has a clearer priority order than one losing 5% to budget and 45% to rank.
Correct answer: B. The average CTR of other advertisers' Shopping ads for similar products — allowing comparison of your CTR against a category-level baseline
Benchmark CTR is a competitive context metric — it tells you whether your Shopping ads are earning clicks at a rate above or below similar products in the market. If your CTR is consistently below benchmark, it usually points to a product title or image quality issue — your ad is appearing but not compelling users to click relative to alternatives. I use this alongside Benchmark CPC to understand whether the issue is competitive (others are bidding higher) or creative (others have more compelling listings).
Correct answer: B. Shopping Auction Insights shows metrics like impression share, overlap rate, and outranking share specifically for Shopping auctions — helping identify which competitors are appearing most frequently for the same product searches
Auction Insights for Shopping shows you which competitors are appearing in the same auctions as your ads, how often you overlap, and how often you outrank them — or they outrank you. It doesn't show specific competitor bids or budgets, but it gives you a directional read on the competitive intensity and which players you're up against most frequently. I use it to explain impression share drops to clients — if a new competitor suddenly appears with 70% impression share in the same auctions, that context reframes the conversation entirely.
Correct answer: B. Review feed quality in Merchant Center Diagnostics, consider increasing bids on key product groups, and check if competitors have entered the auction with stronger listings
Impression share lost to rank is driven by either insufficient bids or insufficient feed/product data quality — since Shopping rank combines both. My diagnostic sequence when I see this: first check Merchant Center Diagnostics for new disapprovals or feed quality warnings, then look at Auction Insights for new competitors, then review whether bids on the affected product groups have become uncompetitive. Rushing to increase bids before fixing a feed quality issue is like throwing money at a problem that better data would solve for free.
Shopping impression share dropping and not sure whether it's a budget problem, a bid problem, or a feed problem? Those three causes need completely different fixes — let me diagnose which one is affecting your account.
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