Sum per month Power Query

• Group by Month/Year
• Advanced Aggregation:
  • Sum of Sales
  • All
• Then re-expand. Since you havethe All column, you will restore the other columns

let

//change next lineto reflect data source
    Source = Excel.CurrentWorkbook(){[Name="Table4"]}[Content],
    #"Changed Type" = Table.TransformColumnTypes(Source,{{"Month", type text}, {"Date", type date}, {"Sales", Int64.Type}}),

//Add year-month column in case sales dates are not always on same day of month
    #"Added Custom" = Table.AddColumn(#"Changed Type", "YearMonth", each Date.ToText([Date],"yyyyMM"), type text),

//Group by year-month
// Then aggregate for All and Sum
    #"Grouped Rows" = Table.Group(#"Added Custom", {"YearMonth"}, {
        {"All", each _, type table [Month=nullable text, Date=nullable date, Sales=nullable number, YearMonth=text]}, 
        {"Monthly Sales", each List.Sum([Sales]), type nullable number}
        }),

//Remove the yearmonth column
    #"Removed Columns" = Table.RemoveColumns(#"Grouped Rows",{"YearMonth"}),

//Re-expand previous columns
    #"Expanded All" = Table.ExpandTableColumn(#"Removed Columns", "All", {"Month", "Date", "Sales"})
in
    #"Expanded All"

Hi Ttaylor9870 ,

Provide another way to think about it.

List.Sum(Table.SelectRows(PreviousStepName,(x)=>x[Month]=[Month])[Sales])

all steps.

let
    Source = Table.FromRows(Json.Document(Binary.Decompress(Binary.FromText("i45W8krMU9JRMtQ31DcyMDICMk2VYnVwCrulJoGFjUDCxiAmkvChBQaG+gbIUrEA", BinaryEncoding.Base64), Compression.Deflate)), let _t = ((type nullable text) meta [Serialized.Text = true]) in type table [Month = _t, Date = _t, Sales = _t]),
    #"Changed Type" = Table.TransformColumnTypes(Source,{{"Month", type text}, {"Date", type date}, {"Sales", Int64.Type}}),
    #"Added Custom" = Table.AddColumn(#"Changed Type", "Sales Total", each List.Sum(Table.SelectRows(#"Changed Type",(x)=>x[Month]=[Month])[Sales]))
in
    #"Added Custom"

Best Regards,
Gao
Community Support Team

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