Expand payment info in several rows

Here is one way to do it.  Please see M code below that transforms your example data into the desired result.  To see how it works, just create a blank query, go to Advanced Editor, and replace the text there with the M code below.

 

 

let
    Source = Table.FromRows(Json.Document(Binary.Decompress(Binary.FromText("nZBLDsQgDEPvgrqsUid8kpyl6v2vUaCU6WKkjmZnA8+22PeQAXBYA9vGsgnYhuFmvJl2vWRxYotdkgkTWMKxXgFaj8U2lBmgj7TSIE6JIjpvpSbU6EFzfqfFC2W+gkjVCZ4n317hiVSDz/wGRVCd+VCDlTS649du74Uw0txGLq5Vepq0vzczZvUtBx3jD9+uiSCdNk4krDdd/uw+Tg==", BinaryEncoding.Base64), Compression.Deflate)), let _t = ((type nullable text) meta [Serialized.Text = true]) in type table [ClientID = _t, Start = _t, End = _t, DurationMonths = _t, #"Monthly $" = _t, #"Total $" = _t]),
    #"Changed Type" = Table.TransformColumnTypes(Source,{{"ClientID", Int64.Type}, {"Start", type text}, {"End", type text}, {"DurationMonths", Int64.Type}, {"Monthly $", Currency.Type}, {"Total $", type text}}),
    #"Changed Type with Locale" = Table.TransformColumnTypes(#"Changed Type", {{"Start", type date}}, "en-150"),
    #"Added Custom" = Table.AddColumn(#"Changed Type with Locale", "Payment Received", each let startdate = [Start] in List.Transform({1..[DurationMonths]}, each Date.AddMonths(startdate, _))),
    #"Expanded DateList" = Table.ExpandListColumn(#"Added Custom", "Payment Received"),
    #"Changed Type1" = Table.TransformColumnTypes(#"Expanded DateList",{{"Payment Received", type date}})
in
    #"Changed Type1"

 

 

Note that I needed a Change Date with locale step since i am in a different locale as you.  You probably won't need that step.

 

If this works for you, please mark it as the solution.  Kudos are appreciated too.  Please let me know if not.

Regards,

Pat