Uploading APC values in group assets

Due to tax legal requirements we are using the group assets concept. We have created a fixed asset and have uploaded takeover values in all the depreciation areas (including tax) using transaction AS91. This asset we have linked to a group asset. However, we are not able to see any value in the group asset (AW01N), nor are we able to load the takeover values in the group assets (AS81) as the APC field is greyed out.

Can somebody please confirm what needs to be done to see the values at the group asset level.

Thanks & Regards,

Sameer