Assortment Share or Share of Assortment is the number of SKUs of a brand (or company) available in a store (or channel) as compared to the total number of SKUs of a brand (or company) in the respective category. So, it gives the share of the SKUs of your brand (or company) present in the store as compared to the category. or It is the share of a brand’s (or company’s) SKUs that are present out of all the SKUs available in that category for consumer choice. Marketers track the assortment share across channels and geographies to track the performance and monitor opportunities and losses against competition.
For example, if the assortment share of Fair & Lovely is low in the Modern Trade outlets, may be there is an opportunity to increase the sales from Modern Trade (though there are many factors to consider). So, it along with other factors gives a key idea to the marketer on what is happening in the store.