{
  "slug": "impression-share-lost-to-rank",
  "name": "Impression share lost to rank",
  "aliases": [
    "Rank-lost impression share",
    "Lost IS (rank)"
  ],
  "definition": "The share of available auction impressions you did not receive specifically because your ad rank was too low.",
  "category": "Paid search",
  "type": "share",
  "unit": "share of available auction impressions (stored 0 to 1, shown as a percent)",
  "direction": "neutral",
  "verification": "review",
  "aggregation": "An unweighted average across keyword-day rows.",
  "grain": "One number per segment and date range, or one row per keyword or campaign.",
  "dimensions": [
    "keyword",
    "campaign_name"
  ],
  "requiredFilters": [
    "segment_id",
    "date_range"
  ],
  "sources": [
    "google-ads"
  ],
  "reports": [
    "paid-search-performance-report"
  ],
  "skills": [
    "paid-efficiency-review",
    "paid-organic-balance"
  ],
  "verbs": [
    "paid_impression_share"
  ],
  "rungs": [
    "R2"
  ],
  "levers": [
    "L8"
  ],
  "questions": [
    "Where are we losing impression share to rank?",
    "Which keywords have fixable auction ground?"
  ],
  "caveats": [
    "The semantic layer averages Google Ads' own per-row rank-lost impression share; nothing is recomputed here.",
    "This is rank-lost only. Impression share lost to BUDGET is not measured anywhere in the product: the budget-lost measures exist in the semantic layer only on a campaign-grain dataset that no tool reads, and the keyword-grain dataset this tool uses has none. A rank-lost figure therefore does not account for the impressions a capped budget cost you.",
    "The tool's own response key drops the rank qualifier, so a consumer reading the raw payload cannot tell which loss reason it has. Always carry the qualifier in the sentence.",
    "Won share and rank-lost share do not sum to one, budget loss and ineligibility live outside both.",
    "Always per segment; unweighted average across rows; stored as a fraction between 0 and 1."
  ],
  "freshness": "~1 day behind, Ads reporting settles overnight; same-day spend is provisional.",
  "failureModes": [
    "Reading a rank-lost number as total lost impression share and concluding the budget is fine.",
    "Adding won share and rank-lost share and expecting 100%.",
    "Reading a rise in rank-lost share as an improvement because a direction oracle painted it green."
  ],
  "notSameAs": [
    {
      "slug": "search-impression-share",
      "why": "One is what you won; this is one named reason for part of what you lost. They are separate averaged columns and do not complement each other."
    }
  ],
  "related": [
    "top-impression-share-lost-to-rank",
    "absolute-top-impression-share-lost-to-rank",
    "search-impression-share"
  ],
  "workflows": [],
  "lastVerified": "2026-08-04"
}