Identify and Note latest version

Hi StevieBeales ,
Sample data
IDReference

IDReference

You can try the following code

let
    Source = Table.FromRows(Json.Document(Binary.Decompress(Binary.FromText("jcxLCoAwDEXRvWTcQD5tk7cIQXBYuv9t2KEoqNPL4Y5B2gyqTaiQiQhnaK287exuzqsozbJYRc+A3djBHcCD+YOFy/XWxNPQ/7BAfrPMjNfbPAE=", BinaryEncoding.Base64), Compression.Deflate)), let _t = ((type nullable text) meta [Serialized.Text = true]) in type table [ID = _t, Reference = _t]),
    GroupedRows = Table.Group(Source, {"Reference"}, {{"MaxID", each List.Max([ID]), type number}}),
    MergedTables = Table.NestedJoin(Source, {"Reference"}, GroupedRows, {"Reference"}, "GroupedRows", JoinKind.LeftOuter),
    ExpandedTable = Table.ExpandTableColumn(MergedTables, "GroupedRows", {"MaxID"}),
    AddedCustom = Table.AddColumn(ExpandedTable, "Label", each if [ID] = [MaxID] then "Latest Version" else null),
    RemovedColumns = Table.RemoveColumns(AddedCustom,{"MaxID"})
in
    RemovedColumns

Final output

Best regards,
Albert He

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