Custom Function to multiply Columns

Hi Mic1979, you are making things complicated - this is not the first time. I've helped you also last time - but you ignored my solution. I give you one more try 😉

Before

After

let
    Source = Table.FromRows(Json.Document(Binary.Decompress(Binary.FromText("i45WcvR1DfJ0dgxW0lEyNAASpgZgFog00DEEk6ZKsTrUUmgEJs2UYmMB", BinaryEncoding.Base64), Compression.Deflate)), let _t = ((type nullable text) meta [Serialized.Text = true]) in type table [Ragion = _t, TOTAL_A = _t, SOME_VALUE = _t, TOTAL_B = _t, #"% INTRODUCTION COEFFICIENT" = _t, #"%" = _t]),
    ChangedType = Table.TransformColumnTypes(Source,{{"TOTAL_A", type number}, {"SOME_VALUE", type number}, {"TOTAL_B", type number}, {"% INTRODUCTION COEFFICIENT", type number}, {"%", type number}}),
    RenamedColumnsDynamic = Table.TransformColumnNames(ChangedType, each Text.Replace(_, "TOTAL", "SMOOTH")),
    MultipliedSmoothColumns = Table.ReplaceValue(RenamedColumnsDynamic,
        each [#"% INTRODUCTION COEFFICIENT"] * [#"%"],
        null,
        (x,y,z)=> x * y,
        List.Select(Table.ColumnNames(RenamedColumnsDynamic), (x)=> Text.StartsWith(x, "SMOOTH")) ),
    RestoredTypes = Value.ReplaceType(MultipliedSmoothColumns, Value.Type(RenamedColumnsDynamic))
in
    RestoredTypes