Running Total with a Reset

Hi, Ashoop2020 ;

You could add index column first.

Then add custom column.

=List.Accumulate(List.FirstN( #"Added Index"[Print Drop Factor],[Index]),0,(state,current)
=> if current=0 then 0 else state + current
)

Delete index column.

The final result:

let
    Source = Table.FromRows(Json.Document(Binary.Decompress(Binary.FromText("i45WMlSK1SGONMArgouNlYwFAA==", BinaryEncoding.Base64), Compression.Deflate)), let _t = ((type nullable text) meta [Serialized.Text = true]) in type table [#"Print Drop Factor " = _t]),
    #"Changed Type" = Table.TransformColumnTypes(Source,{{"Print Drop Factor ", Int64.Type}}),
    #"Renamed Columns" = Table.RenameColumns(#"Changed Type",{{"Print Drop Factor ", "Print Drop Factor"}}),
    #"Added Index" = Table.AddIndexColumn(#"Renamed Columns", "Index", 1, 1, Int64.Type),
    #"Added Custom" = Table.AddColumn(#"Added Index", "Custom", each 
List.Accumulate(List.FirstN( #"Added Index"[Print Drop Factor],[Index]),0,(state,current)
=> if current=0 then 0 else state + current
)),
    #"Removed Columns" = Table.RemoveColumns(#"Added Custom",{"Index"})
in
    #"Removed Columns"

Best Regards,
Community Support Team _ Yalan Wu
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