Hi Doug,
Regarding this issue, I think that we first need to think about what the key factors caused those blank fields in the output matrix report. Apparently the reason is that there are lack of
matched data for some column value and some row value. Assume that the column values are 2002,2003,2004,... and 2008, while the row values are "SubCategory1","SubCategory2" and
"SubCategory3".
If there are only data for (2002, Subcategory1) and (2003, Subcategory1), but no (2004, Subcategory1), then the row with the value Subcategory1 should not be displayed, right?

Unfortunately there is no property that you can set to have the row invisible for a Matrix data region . One method I can think is that you create a T-SQL query with first using PIVOT to
generate same result as the data shown in your matrix and then using an outer SELECT statement to filter those records from the PIVOT query with the condition WHERE column1<>NULL and
column2<>NULL and ... and column20<>NULL.

After that you can create a new dataset with the query and you can use a Table to display the report.

If you want to use Matrix data region, you need to first filter your original dataset to remove the related rows, for example remove all the rows contain Subcategory1 if you could not find any
records for any match (e.g. (2004, Subcategory1)). However I think that either way is not a simple job.

This requirement is indeed complex to be implemented in SSRS. Good luck!

Please feel free to let me know if you have any other questions or concerns. Have a nice day!

Best regards,
Charles Wang
Microsoft Online Community Support
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