Line Graph Based On Date Possible?

I have a question about creating a line graph, here's the scenario:

Once per week I update our inventory quantity in cells B1, B2, B3. I'd like to show these quantities on a graph which compares the quantity with the date. When the quantity gets updated it would automatically add week 2, when the quantity gets updated again it would again expand the graph and add week 3. Is this even possible?

Week 1
A B
Widget 2
Hammer 1
Saw 6

Week 2
A B
Widget 4
Hammer 1
Saw 6