Class A items usually represent about $70-80\%$ of the annual dollar volume $($cost$),$ but are only $15-20\%$ of the items. These are only guideline and the exact amounts will change for different situations, but we are looking for the critical few items, meaning the small number of items that cost the most from an annual perspective. We must take the most care with managing these items in inventory $($forecasting$,$ inventory controls, cycle counting, supplier management, etc$)$ because the mismanagement is very costly$.$

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