Power BI costum column Column, List.Sum “未找到表的列”，为什么？

Question

I am trying to do a running total in PBI, in Power Query.

I have a Sum column, which I created by summing three columns. I created an index.

I used the following "Costum Column":

List.Sum(List.Range(#"Added Index"[Sum],0,[Index]))

I get this error: "Expression.Error: The column 'Sum' of the table wasn't found."

I absolutely do not understand what is causing this.

Here are the power query steps taken below, starting from the creation of my index column:

#"Added Index" = Table.AddIndexColumn(#"Changed Type3", "Index", 1, 1),
    #"Changed Type4" = Table.TransformColumnTypes(#"Added Index",{{"ItalyZ", Int64.Type}}),
    #"Added Custom" = Table.AddColumn(#"Changed Type4", "Sum ItalyZ ItalyY ItalyB", each [Z Italy]+[Y Italy]+[B Italy]),
    #"Changed Type5" = Table.TransformColumnTypes(#"Added Custom",{{"Sum ItalyZ ItalyY ItalyB", Int64.Type}}),
    #"Added Custom1" = Table.AddColumn(#"Changed Type5", "Custom", each List.Sum(List.Range(#"Added Index"[Sum ItalyZ ItalyY ItalyB],0,[Index]))),
    #"Changed Type6" = Table.TransformColumnTypes(#"Added Custom1",{{"Custom", type number}}),
    Custom = #"Changed Type6"{0}[Custom]

Answer 1

I think your problem is that you need to change:

#"Added Custom1" = Table.AddColumn(#"Changed Type5", "Custom", each List.Sum(List.Range(#"Added Index"[Sum ItalyZ ItalyY ItalyB],0,[Index]))),

to:

#"Added Custom1" = Table.AddColumn(#"Changed Type5", "Custom", each List.Sum(List.Range(#"Changed Type5"[Sum ItalyZ ItalyY ItalyB],0,[Index]))),

Note the edit from #"Added Index"[Sum ItalyZ ItalyY ItalyB] to #"Changed Type5"[Sum ItalyZ ItalyY ItalyB]