Calculating average in rows rather than as column

Hi Anonymous , 

You could try below M code to see whether it work or not

let
    Source = Table.FromRows(Json.Document(Binary.Decompress(Binary.FromText("ZcyxDcAwDAPBXVQbsEU5WcZQm/1HiFURApsvvrhzDAtr+nQb9lXccvSLG8iNm5C7bzYv6EIuugC6KpT78AbdkIsuBF0Vyn0t8wc=", BinaryEncoding.Base64), Compression.Deflate)), let _t = ((type text) meta [Serialized.Text = true]) in type table [Date = _t, Company = _t, Return = _t]),
    #"Changed Type" = Table.TransformColumnTypes(Source,{{"Date", type date}, {"Company", type text}, {"Return", Int64.Type}}),
    #"Grouped Rows" = Table.Group(#"Changed Type", {"Date"}, {{"Return", each List.Average([Return]), type number}}),
    #"Added Custom" = Table.AddColumn(#"Grouped Rows", "Company", each "Benchmark"),
    #"Appended Query" = Table.Combine({#"Added Custom", #"Changed Type"})
in
    #"Appended Query"

Best Regards,
Zoe Zhi

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