Pie chart from Largest slice of another pie chart.

Question

Greetings!
I'm trying to come up with a method which will allow me to create a pie chart of the subgroups from the largest slice of an existing pie chart. The "parent" pie chart will change depending upon the parameters given in the report.
declare @dataTable table (category varchar(10), task varchar(10), timeSeconds int)
insert into @dataTable (category, task, timeSeconds)
values
('Alpha','Scrub',100),
('Alpha','Sweep',100),
('Alpha','Polish',100),
('Bravo','Wash',200),
('Bravo','Dry',200),
('Bravo','Fold',200),
('Charlie','Paint',300),
('Charlie','Sand',300),
('Charlie','Spackle',300)
In this example, when a pie chart is produced, Charlie would have the largest slice. I then want to produce a pie chart showing only the tasks contained within the Charlie category, but which has the flexibility to render if the Alpha or Bravo groups are
the largest slice next time.
Thanks

Answer 1

For anyone else attempting the same thing: I wound up bringing in a reference to the largest slice using a subquery in the initial query, and using that column as a filter on the second pie chart.
I was hoping for a solution from within SSRS itself, but settled on that. I'll leave the question open in the hope someone knows how to achieve the same result from within SSRS.