title: SSRS - Start/End Date parameters + Month Summary
body: <p>I'm working with a report that has start and end date parameters that the stakeholder specifies before running the report. It returns volumes split out by department that fall between the start and end date parameters (e.g. 1 week, 2 week etc.)</p>
  <p>I'd like to add a line graph that shows how these volumes change over a month period. The period would be a month leading up to the date specified in the end date parameter. I'm having trouble achieving this because once you've specified the date range on run time it doesn't seem possible to then expand the range for just the chart. I've tried creating a parameter that takes the end date parameter and subtracts a month from it but because the range has already been set this does nothing.</p>
  <p>I only want to use the expanded date range on the graph. The remaining metrics would just cover the specified parameters.</p>
  <p>Hope that makes sense.</p>