Calculate inventory value as of

I am building an Inventory Cube and i need to know how the inventory calculation is done in AX. So far, i got this information(query) from the report titled Inventory value by inventory dimension:

select InventSum.ItemId,

         InventTable.ItemName,

         InventSum.PostedQty,

         InventSum.PostedValue

from InventDim

      inner join InventSum on (InventDim.inventDimId = InventSum.InventDimId)

      left outer join InventTable on (InventSum.ItemId = InventTable.ItemId)

where exists (select *

                    from InventTable

                    where InventTable.ItemId = InventSum.ItemId

                              and not (InventTable.ItemType = 2)

                   )

        -- Criteria for search

        and InventSum.LastUPDDatePhysical <= @Date

        and InventDim.DataAreaId = @Company

        and InventDim.configId = @Configuration

        and InventDim.InventColorId = @Source

        and InventDim.InventSiteId = @Site

        and InventDim.InventLocationId = @Warehouse

        and InventDim.wMSLocationId = @Location

        and InventSum.Closed = @Closed

        and not (InventSum.PostedQty = 0

                     and InventSum.PostedValue = 0)

group by InventSum.ItemId,

            InventTable.ItemName,

            InventSum.PostedQty,

           InventSum.PostedValue

order by InventSum.ItemId

But the problem is when i run this query i get more results than when i run the report "Inventory value by inventory dimension"

Please help me with the query.