Table view does not show correct Measured value

Hi CornelisV 

I find SUMX in your Quantity variable unnecessary since you're simply summing the quantity and not perfroming any other logic before summing.  That aside, please try this:

SUMX (
    -- Iterate over a table and sum the results of an expression
    ADDCOLUMNS (
        -- Add calculated columns to an existing table
        SUMMARIZECOLUMNS (
            Dates[Date],       -- Group by Date
            Code[Code],        -- Group by Code
            "@quantity",       -- Create a temporary column "@quantity"
            CALCULATE ( SUM ( Amount[quantity] ) )  -- Sum Quantity for each Date+Code
        ),
        "@corrected",         -- Add another temporary column "@corrected"
        SWITCH (
            [Code],             -- Check the value of Code
            1006, 0.99,         -- If Code = 1006, multiply by 0.99
            1009, 0.98,         -- If Code = 1009, multiply by 0.98
            1025, 0.99,         -- If Code = 1025, multiply by 0.99
            1                   -- Otherwise, multiply by 1 (no change)
        ) * [@quantity]        -- Apply the correction factor to the quantity
    ),
    [@corrected]               -- Sum the "@corrected" column across all rows
)

Otherwise, please provide a workable sample data (not an image), your expected result from the same sample data and your reasoning behind. You may post a link to Excel or a sanitized copy of your PBIX stored in the cloud.