Split Row based on year/month/length combination

this is a little better

let
    Origine = Table.FromRows(Json.Document(Binary.Decompress(Binary.FromText("i45WSi0uycxVSM4vLlEwVqhMTSwqVtJRMjIwMgBSphXGZkDK0AAMlGJ1gMorSooSIcpTUpOh6qCUoRFID0RpLAA=", BinaryEncoding.Base64), Compression.Deflate)), let _t = ((type nullable text) meta [Serialized.Text = true]) in type table [desc = _t, y = _t, period = _t, amount = _t]),
    mt = Table.TransformColumnTypes(Origine,{{"desc", type text}, {"y", Int64.Type}, {"period", type text}, {"amount", Int64.Type}}),
  
  prds = (startd, length) =>  List.Transform({0..length-1}, each Date.ToText(Date.AddMonths(startd,_),"yyyy/MM")),
  descs = (desc, length) => List.Transform({1 .. length}, each desc & " month " & Text.From(_)),
  tac = Table.AddColumn(
    mt,
    "split",
    each 
      try
        let
          l = Number.From(Text.Split([period], "x"){1}),
          s = Number.From(Text.Split([period], "x"){0}),
          sd=#date(mt[y]{0},s,1),
          tfc=  Table.FromColumns({descs([desc], l),  prds(sd, l), List.Repeat({[amount] / l }, l)},{"desc","date","amount"})
          in Table.SplitColumn(tfc, "date", Splitter.SplitTextByDelimiter("/", QuoteStyle.Csv), {"y","period"}) 
      otherwise   Table.FromRecords({_})   
  ),
    #"Rimosse altre colonne" = Table.SelectColumns(tac,{"split"}),
    #"Tabella split espansa" = Table.ExpandTableColumn(#"Rimosse altre colonne", "split", {"desc", "y", "period", "amount"}, {"desc", "y", "period", "amount"})
in
    #"Tabella split espansa"