How can I summarize the detail of a straight table into a line chart?

[dpstanley_13]

Please be patient, as this is going to be hard to describe.  I have a straight table that accurately produces the number of rows for the past 13 months as defined by the month and year selected. 

I believe my problem is in what I have to do to get the correct number of rows in the table.  Here is the expression for "Reporting Date" as an example:

=If($(vRetentionReportingDateDiff) < 0 or $(vRetentionDaysFromStart) > 395, Null(),Date(Only({<RetentionNumerator = {1}, TermExclude = {0}, ReportingYear=, ReportingMonth=, Reporting_M={">=$(=max(Reporting_M)-13)"}>} ReportingDate)))

Translated, the first variable, $(vRetentionReportingDateDiff), is used to reject any rows from future months than the month selected.  The second variable, $(vRetentionDaysFromStart), rejects other rows for a condition defined by the user.  If either of these conditions are met, the cell will bet set to NULL and will be suppressed from the table.  Unfortunately, I am unable to set these variables in the script because they are determined by the Year and Month selections.

Now I need to translate this into a line chart with a dimension of Month-Year, which I have been unable to do.  I have attached a minimized copy of my dashboard to remove sensitive information, but there should be enough there to understand what I need.  Thanks in advance for your time.