First, you must go to Set Up>Create>Objects>Historical inventory and check the box “Enable Reports”.
Next, save the object. There will be a tab called “Historical Inventory”. On this tab, the user will be given an option to choose a date on which he/she wishes to retrieve the historical inventory and additional filters. The filters are for limiting the scope of items for which the user wishes to receive historical inventory details. The user can choose all items, a specific group of items, or an individual item.
Choosing 12/31/2015, and a specific item will give the user the exact numbers for inventory on that date selected form the item selected. Once the user has made his/her filter selections, he/she will click “Create Historical Inventory” button. This runs a process in batch to find and process the entire history of item(s) which can take up to 10 minutes to complete.
After time has elapsed the user will go to reports and create a new report of the Historical Inventory object, which will display the numbers for the selection requested by the user. This object will continue to hold those historical inventory numbers until the user deletes records in the object. This means multiple historical inventory “runs” can be in the object at the same time as the records are not cleared after every run. It is important that the user generating the report filters it properly to see their most recent or desired subset of the historical inventory data.