Compare values from two dynamically selected columns

Hi, alinamarinbadea 

Thanks for amitchandak's reply. You can try the way from the link, or try to change the data model and then use the following dax.

let
    Source = Table.FromRows(Json.Document(Binary.Decompress(Binary.FromText("i45W8knNSy/JUNJRMjQGEUZAwsQUSBgbKcXqRCuFZ6aAZY2MIWJAJYYgLljSIzUzPaMEJAbSYQrTD1QBkg3N91VwycxNzSvOzM8DCufmohMgVX6pJQrhMHOMQGYYmcBZEIPci/KLixGKTAxh8mCWqQHcNriSdBQcGwsA", BinaryEncoding.Base64), Compression.Deflate)), let _t = ((type nullable text) meta [Serialized.Text = true]) in type table [Attribute = _t, #"Product 1" = _t, #"Product 2" = _t, #"Product 3" = _t, #"Product 4" = _t]),
    #"Changed Type" = Table.TransformColumnTypes(Source,{{"Attribute", type text}, {"Product 1", type text}, {"Product 2", type text}, {"Product 3", type text}, {"Product 4", type text}}),
    #"Unpivoted Columns" = Table.UnpivotOtherColumns(#"Changed Type", {"Attribute"}, "Attribute.1", "Value"),
    #"Renamed Columns" = Table.RenameColumns(#"Unpivoted Columns",{{"Attribute.1", "Product"}}),
    #"Filtered Rows" = Table.SelectRows(#"Renamed Columns", each ([Value] <> "g" and [Value] <> "mm")),
    #"Changed Type1" = Table.TransformColumnTypes(#"Filtered Rows",{{"Value", Int64.Type}})
in
    #"Changed Type1"

First Product = 
VAR _min =
    CALCULATE (
        SELECTEDVALUE ( 'Product'[Value] ),
        FILTER ( 'Product', 'Product'[Product] = MIN ( 'Product'[Product] ) )
    )
RETURN
    _min

Second Product =
VAR _max =
    CALCULATE (
        SELECTEDVALUE ( 'Product'[Value] ),
        FILTER ( 'Product', 'Product'[Product] = MAX ( 'Product'[Product] ) )
    )
RETURN
    _max

diff % = 
VAR _firstProduct =
    CALCULATE (
        SELECTEDVALUE ( 'Product'[Value] ),
        FILTER ( 'Product', 'Product'[Product] = MIN ( 'Product'[Product] ) )
    )
VAR _secondProduct =
    CALCULATE (
        SELECTEDVALUE ( 'Product'[Value] ),
        FILTER ( 'Product', 'Product'[Product] = MAX ( 'Product'[Product] ) )
    )
RETURN
    DIVIDE ( _secondProduct, _firstProduct )

Best Regards,
Yang
Community Support Team

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