[SIZE=1]let
Source = Excel.CurrentWorkbook(){[Name="Table3"]}[Content],
#"Changed Type" = Table.TransformColumnTypes(Source,{{"Column1", type text}, {"Column2", type any}, {"Column3", type any}, {"Column4", type any}, {"Column5", type any}, {"Column6", type any}, {"Column7", type any}, {"Column8", type any}, {"Column9", type any}, {"Column10", type any}, {"Column11", type any}, {"Column12", type any}, {"Column13", type any}, {"Column14", type any}, {"Column15", type any}, {"Column16", type any}, {"Column17", type any}}),
#"Transposed Table" = Table.Transpose(#"Changed Type"),
#"Promoted Headers" = Table.PromoteHeaders(#"Transposed Table", [PromoteAllScalars=true]),
#"Changed Type1" = Table.TransformColumnTypes(#"Promoted Headers",{{"Date", type date}, {"OT", type text}, {"Name1", Int64.Type}, {"Name2", Int64.Type}, {"Name3", Int64.Type}, {"Name4", Int64.Type}, {"Name5", Int64.Type}}),
#"Extracted Month Name" = Table.TransformColumns(#"Changed Type1", {{"Date", each Date.MonthName(_), type text}}),
#"Grouped Rows" = Table.Group(#"Extracted Month Name", {"Date", "OT"}, {{"SUM N1", each List.Sum([Name1]), type number}, {"SUM N2", each List.Sum([Name2]), type number}, {"SUM N3", each List.Sum([Name3]), type number}, {"SUM N4", each List.Sum([Name4]), type number}, {"SUM N5", each List.Sum([Name5]), type number}}),
#"Unpivoted Other Columns" = Table.UnpivotOtherColumns(#"Grouped Rows", {"Date", "OT"}, "Attribute", "Value")
in
#"Unpivoted Other Columns"[/SIZE]