Table Structure For Large List Of Number Fields

Have a look at this screenshot from excel.

Basically I would like to capture the quantity in stock for the above list of phones at many stores.

I started out by adding each phone model as a numeric field in tblStock, because I need to obtain the quantity value for each and every model, for each and every store.

Is there a better way to do this? I was thinking of creating just 2 fields, Model and Quantity, then adding each model as a record, then using that record as a sort of template. I wander what would be the drawbacks of this, since with the first method, if a user needs to add a phone not on the list he would have to modify the table design.