How do I reference a cell in a matrix that performs the aggregate?

Question

Assuming I have a Matrix such as:
Year
Customer Name SUM(sales amount)
... and the text control the aggregate takes place in (the sum function) is named "matrix1_tb_sum"...
After the report is executed, there will be a column for each year.  Let's say 2013 and 2014 both return.
What will be the name of the text control for each year?  If I reference "ReportItems!matrix1_tb_sum.Value" from any scope it returns the value of the "right most" column grouping.  How do I reference other column groupings?
My goal is to add out-of-grouping columns to the right to show additional data, but I don't want to re-type the formulas.  For example, I would add an out-of-group column to the right and add something like:
=ReportItems!matrix1_tb_sum[2014].Value - ReportItems!matrix1_tb_sum[2013].Value
...to show the difference between the two columns without making a SUM IIF.

Answer 1

Hi Mini Button,
Base on your description, you have a matrix in your report which you want to add an aggregation field of the Sales Amount for each year and finally add an column to show the difference between two years. Right?
In Reporting Service, if we want to compare values of two adjacent columns in a matrix, the best way is using custom code to deal with the logic. I have tested in our local environment. In this scenario, we can compare the current value with previous value.
The difference value is always along with columns generated. So we suggest put this column inside of group instead of appending them at the end of the matrix. In this column, we can call the function defined in the custom code. Here are steps and screenshots
for your reference:
Custom code:
Put the custom code into report:
Private queueLength As Integer = 2
Private queueSum As Double = 0
Private queueFull As Boolean = False
Private idChange As String=""
Dim queue As New System.Collections.Generic.Queue(Of Integer)
Public Function CumulativeQueue(ByVal currentValue As Integer,id As String) As Object
Dim removedValue As Double = 0
If idChange <> id then
ClearQueue()
idChange = id
queueSum = 0
queueFull = False
CumulativeQueue(currentValue,id)
Else
If queue.Count >= queueLength Then
removedValue = queue.Dequeue()
End If
queueSum += currentValue
queueSum -= removedValue
queue.Enqueue(currentValue)
If queue.Count < queueLength Then
Return Nothing
ElseIf queue.Count = queueLength And queueFull = False Then
queueFull = True
Return (queueSum-currentValue-currentValue)
Else
Return (queueSum-currentValue-currentValue)
End If
End If
End Function
public function ClearQueue()
Dim i as Integer
Dim n as Integer = Queue.Count-1
for i=n To 0 Step-1
queue.Dequeue()
next i
End function
Click the report Properties and click the “Code” than add above custom code in it, click ok.
Create a matrix based on your information. Put expression into corresponding positions:
Expression in the first row: =IIF(Previous(Fields!Year.Value) is nothing,"",IIF(Previous(Fields!Year.Value) is nothing,1,Previous(Fields!Year.Value))&" - "&Fields!Year.Value)
Expression in the second row: =Code.CumulativeQueue(Fields!SalesAmount.Value,Fields!CustomerName.Value))
Expression in the third row: =Code.CumulativeQueue(sum(Fields!SalesAmount.Value),Fields!CustomerName.Value)
Note : You may need to modify the custom code and expression based on the data type in your dataset.
Save and preview. It looks like below:
Below similar threads are for your reference:
SSRS 2008 R2 - Add moving average to column group
Difference Between the grouped column
If you still have any question, please feel free to ask.
Regards
Vicky Liu