Say the underlying DataSet (which I've called FruitDataSet) looks like this:
I've created a simple report based on this data:
The Fruit Sales % expression is:
=Sum(IIf(Fields!fruit.Value <> "NonFruit", Fields!units.Value, 0))
/ Sum(IIf(Fields!fruit.Value <> "NonFruit", Fields!units.Value, 0), "FruitDataSet")
This gives what I think is the correct results:
There are two things to note about the expression:
By running the
Sum
against anIIf
expression, you can control what gets included in the totals - here I'm setting NonFruit explicitly to 0.By setting the Scope of the aggregate expression, you can get overall totals to use to work out total percentages - in the report I'm getting a total using FruitDataSet and comparing this to the group-level total to get a % value.
The way you're referencing the textbox total is fine; the only other option would be to use an expression each time you want the total - if this is outside a Tablix you would need to explicitly set the Scope, e.g. the DataSet.