Hello Jonathan,
If we can understand your requirement correctly, here is the solution for displaying all the data and having labels on the X axis only for the Fridays:
1. In the Data Groupings >> Categories >> General, we have 3 expressions for Group By:
=YEAR(Fields!SymDate)
=MONTH(Fields!SymDate)
=DAY(Fields!SymDate)
For the Label we have:
=IF( WEEKDAY(FIRST(Fields!SymDate))=5, FORMAT(FIRST(Fields!SymDate), "d", "en-GB"), "")
2. In the Data Groupings >> Categories >> Sorting, we have 3 expressions:
=YEAR(Fields!SymDate)
=MONTH(Fields!SymDate)
=DAY(Fields!SymDate)
3. In the Data Groupings >> Values, we have two values for CloseVal and VolumeVal:
=SUM(Fields!CloseVal)
=SUM(Fields!VolumeVal)
For the second value, from General >> Options, we have selected Display on Axes – Y Axes: Secondary Y
4. In the Chart >> Axes, select Secondary Y and go to the Range tab. Set Inflate Mode to Tick and uncheck the Inflate Range Begin
For this example we have used secondary Y axis for better readability because there is great difference in the values (Close Val and Volume Val).