Variable date range in variable

I have a number of pages in my Power BI report that display counts and sums of data from tables imported by a couple of different systems. I change the date range in the filters of each object to match the most recent week (used for meeting presentation).  Before the meeting I go into each object and set the new date range.  Since my pages combine various counts and sums for two different data sets, I can't simply set the date range on the page or the report. This seems like a great place to have a global variable for StartWeekDate and EndWeekDate. Change them once someplace and use the variable in my filters.  I understand that this is not possible but haven't been creative enough to figure out how to do something similar.  Is there a way in a measure using DAX to pull the start and end dates from a simple temp table where I can edit it each week?