Quantity field is not updating in AUC after partial capitalization

Dear colleagues,

Could you please advice is it standard SAP behavior that after partial capitalization the quantity field in AUC master data is not updated.

For example I have AUC master data created for 2 pcs of equipment in one record:

I'm creating settlement rule for only one pcs in AIAB:

After posting of capitalization the quantity field in AUC master data doesn't change, it still shows 2 pcs, although the asset value became smaller.

Seems that it's a normal system behavior, but maybe someone can explain it from SAP technical point of view.

Thank you

Marianna