Charts are not filtered for null values
I have chart which uses an aggregate model and displays values for different Regions. When I click on any region on the chart, it filters model to show data for the selected region only. There are some records where Region is blank so chart group them under "null" category. The problem is that when I click on null category on the chart, it does not filter model where Region is null. Is that the standard behavior? Can this be fixed?