Slicer that does not affect a value on X-axis for comparisons

Hi Aimeeclaird ,

parry2k ‘s post is in detail. Only as a supplement, I created a new table similar with his blog:

New table =
ADDCOLUMNS (
    UNION ( { "National Average" }, VALUES ( 'Table'[School] ) ),
    "Average",
        IF (
            [Value] = "National Average",
            AVERAGE ( 'Table'[Average] ),
            CALCULATE (
                AVERAGE ( 'Table'[Average] ),
                FILTER ( 'Table', [School] = [Value] )
            )
        )
)

Here is the final output:

Actually I am not clear about this :Would you be able to advise of a solution that doesn't involve having the actuals as a value. We need to calculate the 'actual' based on all data in the data table. 

Please explain more or provide us with your expected output.

Best Regards,
Eyelyn Qin
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