What is a spare part ABC classification A,B,C classifying method of spare parts

Spare parts ABC classification A, B, C classifying method of spare parts refers to: According to the number of spare parts and the amount of funds to be classified, that is, all spare parts are divided into A, B, C three categories. Usually, there are few types of A spare parts (approx. 10%), and more funds are used (about 50%~70%); there are many kinds of B type spare parts (about 25%), and the funds are small (about 20%~30%); C There are many types of spare parts (about 65%), but the funds are very small (about 10%~20%)