Summarize table by column

So try this.

Right click create new query >> blank query

Go to 'Advanced Editor' for this query and select all and paste in the below. 

Then follow these steps again for option 2. Pick the one that works best for you. I think option 2.

Option 1

let
    Source = Table.FromRows(
        Json.Document(
            Binary.Decompress(
                Binary.FromText(
                    "i45WCjRUMDIwMlSAAkOlWJ1oJTBBlowRSMYAJmNKhgxu00yQZIxBMkZwPQbkSKE4Ao+UCYorUBxILalYAA==",
                    BinaryEncoding.Base64
                ),
                Compression.Deflate
            )
        ),
        let
            _t = ((type nullable text) meta [Serialized.Text = true])
        in
            type table [Column1 = _t]
    ),
    #"Filtered Rows" = Table.SelectRows(Source, each ([Column1] <> "")),
    #"Extracted First Characters" = Table.TransformColumns(
        #"Filtered Rows", {{"Column1", each Text.Start(_, 7), type text}}
    ),
    #"Renamed Columns" = Table.RenameColumns(#"Extracted First Characters", {{"Column1", "Quarter"}}),
    #"1" = Table.AddColumn(#"Renamed Columns", "1", each Number.RandomBetween(0.5, 15.3), Decimal.Type),
    #"2" = Table.AddColumn(#"1", "2", each Number.RandomBetween(0.5, 15.3), Decimal.Type),
    #"3" = Table.AddColumn(#"2", "3", each Number.RandomBetween(0.5, 15.3), Decimal.Type),
    #"4" = Table.AddColumn(#"3", "4", each Number.RandomBetween(0.5, 15.3), Decimal.Type),
    #"5" = Table.AddColumn(#"4", "5", each Number.RandomBetween(0.5, 15.3), Decimal.Type),
    #"Grouped Rows" = Table.Group(
        #"5",
        {"Quarter"},
        {
            {"1", each List.Sum([1]), type number},
            {"2", each List.Sum([2]), type number},
            {"3", each List.Sum([3]), type number},
            {"4", each List.Sum([4]), type number},
            {"5", each List.Sum([5]), type number}
        }
    )
in
    #"Grouped Rows"

Option 2

let
    Source = Table.FromRows(
        Json.Document(
            Binary.Decompress(
                Binary.FromText(
                    "i45WCjRUMDIwMlSAAkOlWJ1oJTBBlowRSMYAJmNKhgxu00yQZIxBMkZwPQbkSKE4Ao+UCYorUBxILalYAA==",
                    BinaryEncoding.Base64
                ),
                Compression.Deflate
            )
        ),
        let
            _t = ((type nullable text) meta [Serialized.Text = true])
        in
            type table [Column1 = _t]
    ),
    #"Filtered Rows" = Table.SelectRows(Source, each ([Column1] <> "")),
    #"Extracted First Characters" = Table.TransformColumns(
        #"Filtered Rows", {{"Column1", each Text.Start(_, 7), type text}}
    ),
    #"Renamed Columns" = Table.RenameColumns(#"Extracted First Characters", {{"Column1", "Quarter"}}),
    #"1" = Table.AddColumn(#"Renamed Columns", "1", each Number.RandomBetween(0.5, 15.3), Decimal.Type),
    #"2" = Table.AddColumn(#"1", "2", each Number.RandomBetween(0.5, 15.3), Decimal.Type),
    #"3" = Table.AddColumn(#"2", "3", each Number.RandomBetween(0.5, 15.3), Decimal.Type),
    #"4" = Table.AddColumn(#"3", "4", each Number.RandomBetween(0.5, 15.3), Decimal.Type),
    #"5" = Table.AddColumn(#"4", "5", each Number.RandomBetween(0.5, 15.3), Decimal.Type),
    #"Unpivoted Other Columns" = Table.UnpivotOtherColumns(#"5", {"Quarter"}, "Attribute", "Value"),
    #"Grouped Rows" = Table.Group(
        #"Unpivoted Other Columns", {"Quarter", "Attribute"}, {{"v", each List.Sum([Value]), type number}}
    )
in
    #"Grouped Rows"

I think this should give you a better understanding of what I was trying to explain.