Step 1 Create a data source and a dataset
Step 2
Add an extra field for the Running total.
Add an expression.
Step 3
Go to Common Functions > RunningValue
Add RunningValue function
Add field you want the create running total for. (Fields!Units.Value)
Add a name of the aggregate function (SUM)
Specify the scope as string, means, it needs to be in double quotes. In this case it is the whole dataset ("DataSet1")
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Step 4
I have a field called Region and I want to create a running total by region.
4.1 Add the Region column into the table.
4.2 If you want to create the running total by region, the data need to be grouped by Region first. Otherwise you will get an error.
Step 5
Add a column for cumUnitsByRegion, add expression.
Step 6:
Use RunnigValue function to create the running total by Region.
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If you are creating a running total by a subcategory, data needs to be grouped by the subcategory first.