Do you want to group Inventory report by Warehouse and Inventory Item group code like that?
This is the report template I’ve used.
[Inventory Report 2:4, 2,1]
@{REPORT CONSUMPTION DETAILS:C.Warehouse.asc::,}
@{REPORT CONSUMPTION DETAILS:I.GroupCode.asc::,}
>>$1
>$2
{REPORT CONSUMPTION DETAILS:C.Name.asc,C.Prediction,C.Unit:(PCW=$1) and I.GroupCode="$2"}