Matrix total - turn into %

hi, Anonymous 

Based on my research, You could try this way as below:

Step1:

Create a dim Score table like this:

Add an additional value "A" in it.

Step2:

Create the relationship between them as below:

Step3:

Create a measure like this

Measure 2 = 
IF (
    CALCULATE ( MIN ( 'Dim'[Score] ) ) = "A",
    FORMAT (
        DIVIDE (
            CALCULATE ( COUNTA ( 'Table'[Score] ), 'Table'[Score] = "Met" ),
            CALCULATE ( COUNTA ( 'Table'[Score] ) )
        ),
        "Percent"
    ),
    CALCULATE ( COUNTA ( 'Table'[Score] ) )
)

Step4:

Drag Score from dim table and measure into matrix visual

Result:

and here is pbix file, please try it.

Best Regards,

Lin