1. Let’s say you have two warehouse locations, A and B. 
   
2. You received inventory for item 123 with a qty. of 10 to location A 365 days ago.  It is sitting there, not selling.  It shows up on the aging report with an age of 365 days. 
3. Someone transfers this item 123, qty. of 10, to location B today. 
4. If you run the inventory aging by location, it will show that location A for item 123 has a zero qty, so the age is zero.  It will show that location B for this item has a qty. of 10, and the age is also zero because you just transferred it to location B today.  You can see there’s something wrong here. 

The paradox in number 4 above shows that there’s a flaw in inventory aging by location.  But there’s not much we can do about it. 

On the other hand, if you print inventory aging by another sequence (e.g., by item) and you choose to print all locations, then we treat all location transactions as a whole and ignore the transfer between locations.  As a result, we will show the inventory aging for item 123 as 365 days.  If you choose to print only one location, then you will have the same issue. As long as you understand there's a limitation in the inventory aging report by location sequence (i.e., the age days may be incorrect due to transfer), you can use the "by location" inventory aging report with this limitation.  

Since inventory aging by location may be incorrect, is there ever a reason to use Inventory Aging Report by Location?  Yes, there is. For example, you can't go back in time to print an Elliott inventory stock status report as of a certain date, so some users like to run an Inventory Aging Report as of a specified date as a way to produce a past inventory stock status report.

Please also refer to the other similar Knowledge Base article about inventory aging for one or all locations:

http://support.elliott.com/knowledgebase/articles/412351-inventory-aging-report-shows-different-age-between