Definition of allowance for English Language Learners. : 1  an amount of money that is given to someone regularly or for a specific purpose. : 2  a small amount of money that is regularly given to children by their parents. : 3  an amount of something (such as time) that is allowed or available.
category development index (CDI) Category development index (CDI) is an index that is calculated by taking the percentage of a product categoryâs total sales that occur in a given market area as compared to the percentage of the total population in the market.
Category Development Index. Category Development Index (CDI) measures the sales performance of a category of goods or services within a specific group, compared with its average performance among all consumers. By definition, CDI measures the sales strength of a particular product category within a specific market (e.g., soft drinks in 10â50 year old's). 1 Purpose.