How to combine aggregates within a group with aggregates across groups within SSRS

Question

With this dataset:

Category | Amount
A        | 5
A        | 3
B        | 6
B        | 2
B        | 1
C        | 7

I want to create a tabli

Answer 1

You could have used Scope descriptors to identify the groups that the SUM is to be run against:

• Category group is defined in tablix Row Groups.
• DataSet1 is the name of the dataset.

Grouped Amount: [Sum(Amount)]

Dataset Total: SUM(Fields!Amount.Value, "DataSet1")

Percentage: SUM(Fields!Amount.Value, "Category") /SUM(Fields!Amount.Value, "DataSet1")