Need help to get the conditional average in power query

Hi, Fowmy's solution surely works. When your dataset consists of 2k+ rows, you might try this,

let
    Source = Table.FromRows(Json.Document(Binary.Decompress(Binary.FromText("i45WCg1W0lEyNFCK1YGxTRFsIyQ2VIk3SBiJDVPuDVfiGIrKNERmQ1Q7OyLEwWwgMxYA", BinaryEncoding.Base64), Compression.Deflate)), let _t = ((type nullable text) meta [Serialized.Text = true]) in type table [Country = _t, Value = _t]),

    #"Added Custom" = Table.AddColumn(Source, "Custom", each Table.Group(Source, {"Country"}, {{"grouped", each _}}){[Country = [Country]]}[grouped][Value]),
    Avg = Table.TransformColumns(#"Added Custom", {{"Custom", each List.Average(List.RemoveItems(List.Transform(_, Number.From), {0}))}})
in
    Avg

Hello

the simplest thing is to include all in ONE Group-Step... the average except 0 and All rows (to keep the value-column for later)

Check it out

let
    Source = Table.FromRows(Json.Document(Binary.Decompress(Binary.FromText("i45WCg1W0lEyNFCK1YGxTRFsIyQ2VIk3SBiJDVPuDVfiGIrKNERmQ1Q7OyLEwWwgMxYA", BinaryEncoding.Base64), Compression.Deflate)), let _t = ((type nullable text) meta [Serialized.Text = true]) in type table [Country = _t, Value = _t]),
    #"Changed Type" = Table.TransformColumnTypes(Source,{{"Value", type number}}),
    #"Grouped Rows" = Table.Group(#"Changed Type", {"Country"}, {{"Average", each List.Average(List.Select([Value], each _ >0)), type number}, {"AllRows", each _, type table [Country=text, Value=number]}}),
    #"Expanded AllRows" = Table.ExpandTableColumn(#"Grouped Rows", "AllRows", {"Value"}, {"Value"})
in
    #"Expanded AllRows"

This function of the group-function makes the average without 0

{"Average", each List.Average(List.Select([Value], each _ >0)), type number}

Copy paste this code to the advanced editor in a new blank query to see how the solution works.

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Kudoes are nice too

Have fun

Jimmy