Expressions are evaluated against the data scopes
To be able to use the data fields that are defined in the different data scope you can use data functions
. You can only specify the current scope or a containing scope, you cannot specify a scope that is lower or at the same level in containment order than the current scope.
In your scenario, the data is bound to report's inner data item(table) and it will not be possible to reach the table's data scope inside the GroupFooter section as it will not be in the containing scope.
Check if binding the data source to report instead of the Table item can be applied in your scenario.
Another approach can be to place another data item
inside the GroupFooter section and bind it to the same data source as table uses.
Standalone Designer does not support saving the values of one report item and using them for another report item, it can be done only programmatically.
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