All markets · 7-day comparable periods
Empty time buckets are shown as zero and retain their sample size; they are not interpolated by AI.
These are the records counted in the current prevalence numerator.
Mara Voss
Inspect evidenceElias North
Inspect evidencePsychological decreased from 100% to 50% across comparable 7-day windows, a 50 percentage-point downward movement. The current matches are concentrated in Amazon New Releases.
Amazon New Releases has the highest current prevalence at 100% (2 of 2), while Amazon Bestsellers is lowest at 0% (0 of 2).
Inspect the matching covers alongside non-matching covers from the same source types. Look for whether psychological co-occurs with particular typography, imagery, colour, or subgenre choices before treating this as a durable convention.
Current window: 2 matching covers from a sample of 4.
Previous window: 2 matching covers from a sample of 2.
50 percentage points of measured downward movement.
This describes the tracked genre sample only. It does not establish why the feature changed, whether it improves sales, or whether it represents the entire book-cover market.