Capacity Usage in MMR

Hi Experts,

I am not getting the exact purpose of "Capacity Usage" field which we define in Material Master ?

If the Total capacity of bin is 100 & capacity usage is 11 .

I am placing 9 pcs of material in bin 01-01-01(Total capacity =100).

So now what will be remaining qty ?

Does the capacity usage = weight of each material ?

Please post your opinion.