Group By Week Starting Monday?

[kestefon]

I have a query (a rather large one that includes multiple outer joins) comprised of weekly data. Some of the different tables I've combined defined their week at a different start date. So, for instance, Table A starts its weeks on Sundays, while Table B starts its weeks on Mondays, etc.

I've already joined the tables into one combined query, so I'm wondering if there's an adjustment I could make to it that would roll all of the dates up into weeks starting on Monday? For example: If there are separate records for 2/3 and 2/4 and 2/5, I would want to aggregate that as 2/3/14.

Lastly, the layout of my query is: Period, Field1, Field2, etc.

[ItsMe]

You are trying to count periods where period one is the first week in a calendar year?