Calculate cumulative reverse

Hello danilomorganti 

 

you can try this approach but it doesn't look on the date but really on the prior cell value. It basically adds a new column with the cumulative-column but shifted down by one row. After that a new column is added where your needed calculation takes place

Here a code example

let
    Source = Table.FromRows(Json.Document(Binary.Decompress(Binary.FromText("Tc27DQAhDATRXhwjnT8Y3Aui/zbO0hKsNNFL5hxR+zpXNxmickeTE9mzYEvYJPOAJVlM2CLLBdtku2BFVv24Pw==", BinaryEncoding.Base64), Compression.Deflate)), let _t = ((type nullable text) meta [Serialized.Text = true]) in type table [Date = _t, Cumulative = _t]),
    #"Changed Type" = Table.TransformColumnTypes(Source,{{"Date", type date}, {"Cumulative", Int64.Type}}),
    GetNewColumnWithPreviousValue = Table.FromColumns
    (
        Table.ToColumns(#"Changed Type")&{{0}&List.RemoveLastN(#"Changed Type"[Cumulative])},
        Table.ColumnNames(#"Changed Type")&{"CumulativeShifted"}
    ),
    #"Added Custom" = Table.AddColumn(GetNewColumnWithPreviousValue, "Result", each [Cumulative]-[CumulativeShifted]),
    #"Removed Columns" = Table.RemoveColumns(#"Added Custom",{"CumulativeShifted"})
in
    #"Removed Columns"

Result

Copy paste this code to the advanced editor in a new blank query to see how the solution works.

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Have fun

Jimmy

Hi, danilomorganti 

 

Based on your description, I created data to reproduce your scenario. The pbix file is attached in the end.

Table:

 

You may create a custom column as below.

let
tab=Table.SelectRows(#"Changed Type",(x)=>Date.Month(x[Date])=Date.Month([Date]) and x[Date]<[Date]),
m=try [Cumulative]-Table.Max(tab,"Date")[Cumulative] otherwise [Cumulative]-0
in 
m

 

Result:

 

Best Regards

Allan

 

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