Supply Chain
Demand is a bell curve, cartons hold whole garments. Something always gets rounded, and it is always a tail size.
— points
Worst gap between packed ratio and demand share
The four shares should sum to 100; if they do not, the allocation still fills the carton but the deviations are measured against a curve that does not exist and mean nothing. A larger carton always tracks the demand curve more closely — the deviation falls roughly as one over carton size — so where handling permits it, a bigger ratio pack is the cheapest fix for assortment error. Ratio packs also assume every store wants the same curve, which is the real limitation: stores differ by demographic and climate, and a single national ratio guarantees markdown at both tails somewhere.
Garment Assortment Pack-Ratio Generator — free, with the formula and a worked example, at Textile School.