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.
Understanding BDI and CDI Formulas. BDI and CDI are indices comparing the relative strength of a market to overall sales. The Brand Development Index (BDI) is an index compared to overall brand sales. The Category Development Index (CDI) is an index compared to overall category sales. Like any index, a score of 100 is average.