Tracking how long items are in stock from list of entries

[MarcelPadu]

I have a table that tells me what items enter the stock, when and how many. Could I somehow track for individual items that are still in stock the date at which they entered?

It must be said that after some time things get sold,  so if I had 10 balls enter today and I sell 7 and resupply 7 balls 5 days later, I should see 3 balls from 5 days ago and 7 from today.

Closest I got to make it possible was to make a table where every entry is a single item with its date so i whould have 10 duplicate entries and remove then add 7 of them by numbering the entries 1 to 10 then using a where cause >7 but it has to be mapped per item?? I rly dont think Qlik can handle so much.

[MarcelPadu]

I forgot to say theres also a lost of sold items with date quantity and item type. I use it to remove from the entries. Also, the oldest entries should be eliminated first like the oldest 3 balls in the stock if I sell 3.