Period Average Cost Results

Hi,

We run our inventory via Average Costing method.

We want to create a report which tracks the average cost per reporting period (in our case, 4 week periods).

I know the Average Cost is a calculation of the stock on hand vs it's cost, so I would assume it would be one mighty formula to have these averages across a sheet by period for each Item? :?:

Any suggestions?

TIA

Stuart