Dummy variable problem

Cognos Use Power Query for this kind of transformation:

let
    Source = Table.FromRows(Json.Document(Binary.Decompress(Binary.FromText("XYwxDoAgDEWvYjoz2EILB2BxYDTREOL9byGVRoxDf35eX1srLODgoB55L+W88G2TeVWCBkNzFbbcO5L3ytBmHUxRYBYxk0z9Wg/isTBNz1iCGdPyI9E0PZKYYvq/Gx4RtHYD", BinaryEncoding.Base64), Compression.Deflate)), let _t = ((type nullable text) meta [Serialized.Text = true]) in type table [#"(blank)" = _t, #"(blank).1" = _t, #"(blank).2" = _t, #"(blank).3" = _t, #"(blank).4" = _t, #"(blank).5" = _t, #"(blank).6" = _t]),
    #"Changed Type" = Table.TransformColumnTypes(Source,{{"(blank)", type text}, {"(blank).1", type text}, {"(blank).2", type text}, {"(blank).3", type text}, {"(blank).4", type text}, {"(blank).5", type text}, {"(blank).6", type text}}),
    #"Removed Other Columns" = Table.SelectColumns(#"Changed Type",{"(blank)", "(blank).2", "(blank).3", "(blank).4"}),
    #"Promoted Headers" = Table.PromoteHeaders(#"Removed Other Columns", [PromoteAllScalars=true]),
    #"Changed Type1" = Table.TransformColumnTypes(#"Promoted Headers",{{" ", type text}, {"DUMMY_1", Int64.Type}, {"DUMMY_2", Int64.Type}, {"DUMMY_3", Int64.Type}}),
    #"Unpivoted Other Columns" = Table.UnpivotOtherColumns(#"Changed Type1", {" "}, "Attribute", "Value"),
    #"Removed Columns" = Table.RemoveColumns(#"Unpivoted Other Columns",{" "}),
    #"Grouped Rows" = Table.Group(#"Removed Columns", {"Attribute"}, {{"Count", each List.Sum([Value]), type number}})
in
    #"Grouped Rows"