Can't use Cascading as an axis in the Two Dimensional Filer Statistics portlet. Ideally it would have a row or column for each combination of options. For example, if the cascading select had:

• Option 1
  • sub-option a
  • sub-option b
• Option 2
  • sub-option x
  • sub-option y

... Then you would have a row/column each for Option 1 - sub-option a, Option 2 - sub-option b, Option 2- sub-option x, Option 2 - sub-option y. Not sure if this was intended behavior (making this an improvement request instead of a bug), or if it was actually an oversight, so please classify it as you think best.

Steps to see this:

• Create a custom field of type Cascading Select, adding some options
• Create a few issues which have this field populated
• Save a filter that includes these issues
• Try to add a Two Dimensional Filter Statistics portlet that has your cascading select on one axis. It won't be available as an option. However, if you have, for example, a select list custom field, that will be available.