Add month column repeated by year using dax

[nicolasvc]

I have a table in the sample the value of a product per year, from 2022 to 2025, and I would like to add the month column, in which it is repeated every month for every year. This can be done but only for a table that is one year old, and since it is several years old, I do not know how to repeat the procedure.

Year	Product	Value
2022	A	100
2022	B	1000
...	...	...
2023	A	800
2023	B	500
...	...	...
2025	B	300
...	...	...

Result table:

Year	Month	Product	Value
2022	1	A	100
2022	1	B	1000
...	...	...	...
2022	2	A	100
...
2025	12	B	300
...	...	...	...

[mahoneypat · Accepted solution]

Here's one way to do it in the query editor.  To see how it works, just create a blank query, open the Advanced Editor and replace the text there with the M code below.  You just need to add a custom column with {1..12} and then expand that to new rows.

let
    Source = Table.FromRows(Json.Document(Binary.Decompress(Binary.FromText("i45WMjIwMlTSUXIEYkMDA6VYHbiQExAbIYSMoKqMUYVAqkxAQrEA", BinaryEncoding.Base64), Compression.Deflate)), let _t = ((type nullable text) meta [Serialized.Text = true]) in type table [Year = _t, Product = _t, Value = _t]),
    #"Changed Type" = Table.TransformColumnTypes(Source,{{"Year", Int64.Type}, {"Product", type text}, {"Value", Int64.Type}}),
    #"Added Custom" = Table.AddColumn(#"Changed Type", "Month", each {1..12}),
    #"Expanded Month" = Table.ExpandListColumn(#"Added Custom", "Month"),
    #"Changed Type1" = Table.TransformColumnTypes(#"Expanded Month",{{"Month", Int64.Type}})
in
    #"Changed Type1"

Pat

[nicolasvc]

Thanks for the help! I would have liked it in DAX, but I managed to change a few things to be able to use this solution in PQ!

[VahidDM]

Hi @nicolasvc 

Is that value for 2025-12-B  in the result table correct?

Appreciate your Kudos!!

[nicolasvc]

Hi @VahidDM! No, I already edited the table. Thanks.