Change blank by earliest text value per week

Hi joshua1990 ,

Hope it helps.

let
  Source = Table.FromRows(
    Json.Document(
      Binary.Decompress(
        Binary.FromText("i45WMjIwMtY1MFTSUQJhBM9UKVYHWdYIiPNKc3KAlJlSbCwA", BinaryEncoding.Base64), 
        Compression.Deflate
      )
    ), 
    let
      _t = ((type nullable text) meta [Serialized.Text = true])
    in
      type table [#"Archival Year-Week" = _t, Order = _t, #"Year-Week" = _t, Value = _t]
  ), 
  #"Changed Type" = Table.TransformColumnTypes(
    Source, 
    {
      {"Archival Year-Week", type date}, 
      {"Order", Int64.Type}, 
      {"Year-Week", type date}, 
      {"Value", Int64.Type}
    }
  ), 
  Custom1 = Table.TransformColumns(
    #"Changed Type", 
    {
      "Year-Week", 
      each 
        if _ <> null then
          _
        else
          Table.Group(
            #"Changed Type", 
            {"Archival Year-Week"}, 
            {{"Min", each List.Min([#"Archival Year-Week"])}}
          )[Min]{0}
    }
  )
in
  Custom1

Best Regards,
Gao
Community Support Team

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