Organization of Table By Time

I have created a matrix table with rows consiting of dates, columns being variaties of a product, and the values holding the quanitites. The table is suppose to show a 4 section, week by week comaprison between the rows. I need the table to be able to take the current date of when report is acceded and use that for the starting date for the first week/row then produce the information the next 3 week/rows. I filtered to sort to show the last 4 weeks including today's date but each row goes day by day. How can I create a matrix like the one I need.