Reporting, Metrics Interpretation, and Attribution Windows
Metrics and how they chain
Impressions lead to clicks (CTR), clicks to orders (CVR), orders to sales, alongside CPC, spend, ACOS (spend ÷ attributed sales), ROAS (the reciprocal of ACOS) and TACOS (ad spend ÷ total sales, paid plus organic). Each metric localises a problem: weak impressions point to bids, budget or targeting; weak CTR to targeting relevance or creative; weak CVR to the detail page, price or reviews; weak ACOS to all of the above plus margin.
Attribution
Amazon credits a sale to an ad when the customer clicks and buys within a fixed window, and the window differs by ad product - commonly 7 days for Sponsored Products and 14 days for Sponsored Brands and Sponsored Display, with view-through credit handled separately. Attributed sales are not total sales, and a single sale is claimed once by the winning ad. Compare periods using the same window, and remember that long consideration cycles favour longer windows.
Reports that answer questions
Search-term report: what customers actually typed. Targeting report: keyword and ASIN performance. Placement report: top of search versus product pages versus rest. Purchased-product report: halo and cross-sell. Business reports and Brand Analytics supply the organic and market context that ad reports cannot.
Traps
Judging a campaign on ACOS without TACOS context, reading a 7-day export against a 14-day benchmark, assuming zero attributed sales means zero effect, and treating new-to-brand orders as incremental without checking repeat purchase behaviour.
Rule of thumb
Diagnose in order - impressions, CTR, CVR, ACOS - and change one lever at a time, waiting for enough clicks (roughly 100 per ad group) before drawing conclusions.