On what basis I should enter the ITEM % / Sequence No. into the Assig Item form of ABC Group Assignm

HI ALL, I have create an ABC Compile criteria is Current On hand Quanity and Cmpile it too it is at Organization Level. Now i am Craeted the ABC Classes as well, Thereafter when i am trying to create the ABC Group Assignment so I am not getting how to and on what basis me devide mine Current On hand Quantity among the ABC ?? There is four things say SEQUENCE, VALUE, ITEM % ?? I am not getting what should mean by Item % ?? simialarly i am not getting what should meant by the Sequence No. ??

I have gone through the documentation so it entaisl while compiling we have abc descendeing value report on the basis of them i can classify but agian the same question, I would have for that in mine IO there are billions of Item and this Report showing me the from  1 (sequence no) up to the end ??