Grouping issues according to the week their due date falls in

Hello,
I am trying to create stacked bar graph showing Resolved vs Unresolved issues since the start of the year. The issues need to be grouped into bars defined by the week in which the issues’ Dues Dates fall (for example, all issues with a Due Date from April 6 - April 12 would be grouped together). I’m having trouble with grouping the issues this way and would appreciate some guidance on how I might accomplish this.