making an auto self updating chart

Hi,
I am looking for a solution and did not find it yet.
I want to make an excel workbook as follows:

every week, I import a sheet that has the same pre built structure, but different data.
Basically, each sheet is a snapshot/status report of a product's market for that specific moment.

What I want to do, is to create another sheet with a chart/graph that is showing the progress from week 1 to the next week and so on, and each time I add a new snapshot sheet, it(the chart/graph) will automatically update.
I want to do this in order to track the changes in the market.

any ideas any body?

Thank you Keebellah,
I attached an example.
Lets say I would like to track the reviews generation rate of each product.