These are the bottom 20 performing stores during the promotion. These geographically disbursed stores accounted for only 15% of total promoted unit sales. We also see that more than half of these stores belong to store class B.
The unit sales by store & weekday graph highlights the contrast between unit sales (represented by the colored circles) between stores on any given day. Stores are sorted by unit sales within each store class, so "problem stores" within each store class are ones near the end of the list within each store class.
The indexed DSI by weekday graphic introduces a new metric: the indexed daily sales index. Individual store performance is indexed against all store performance for each weekday during the promotion. Most "Bottom 20" stores performed at between 40% and 60% of the level of the "Top 20" stores on a given weekday, while a small number of stores performed at between 10% and 30% of the "Top 20" storesà level.