Inventory Aging Query help?

[Poolcue]

I have 2 tables that I want to use to create a query with and do not know the
best way to do it.

Table 1 holds my inventory item field with a total on hand field. I get
this information from a query dump from another system.

Table 2 has records of all of my PO recevings with the date rec, the item
name and the quantity received on this date. I get this information from a
query dump from another system also.


I want to get the quantity of items I have on hand from the LIFO method so I
always am counting the newest inventory as in stock.

Example:
I have 100 tires on hand right now in table 1.

I have 20 receiving records in table 2 for this item where I have them
sorted from newest receipt to oldest.
Record 1 received 50 to stock on 4-1-2009
Record 2 received 25 to stock on 2-1-2009
Record 3 received 100 to stock on 1-1 2009
Record 4 received 50 to stock on 12-1-2008

I need to have a query that will give me records for each of the receipts
that are in stock to determine the aging for the items in stock.

Having 100 in stock would tell me that I have
50 tires dated 4-1-2009
25 tires dated 2-1-2009
and 25 tires dated 1-1-2009

Any ideas?