How to Subtract Data From Same Column In Imported Table When Put In Matrix?

Hi sv98917n 

You may achieve your goal by Power Query Editor or build a measure.

Your data model may like below.

Measure:

Measure = 
Var _2021 = CALCULATE(SUM('Table'[Value]),FILTER(ALL('Table'),'Table'[Year]= MAX('Table'[Year])&& 'Table'[Date Alias]=MAX('Table'[Date Alias])))
Var _2020 = CALCULATE(SUM('Table'[Value]),FILTER(ALL('Table'),'Table'[Year]= MAX('Table'[Year])-1&& 'Table'[Date Alias]=MAX('Table'[Date Alias])))
Return
IF(SUM('Table'[Year])=2021,_2021-_2020,BLANK())

However, this result may looks not very well.(It will show measure result for each year, we just need the result right beside 2021)

So you may do some transform in Power Query Editor.

Duplicate Table, and pivote the Year Column and add a custom column.

let
    Source = Table.FromRows(Json.Document(Binary.Decompress(Binary.FromText("i45WMjIwMlDSUfIqzak0BNKm5kqxOmBRQyRRQzNDmDBMsRFI2NQSXTVI2MjYQCk2FgA=", BinaryEncoding.Base64), Compression.Deflate)), let _t = ((type nullable text) meta [Serialized.Text = true]) in type table [Year = _t, #"Date Alias" = _t, Value = _t]),
    #"Changed Type" = Table.TransformColumnTypes(Source,{{"Date Alias", type text}, {"Value", Int64.Type}}),
    #"Pivoted Column" = Table.Pivot(#"Changed Type", List.Distinct(#"Changed Type"[Year]), "Year", "Value"),
    #"Added Custom" = Table.AddColumn(#"Pivoted Column", "Subtract", each [2021]-[2020]),
    #"Changed Type1" = Table.TransformColumnTypes(#"Added Custom",{{"Subtract", Int64.Type}})
in
    #"Changed Type1"

Result:

You can download the pbix file from this link: How to Subtract Data From Same Column In Imported Table When Put In Matrix?

Best Regards,

Rico Zhou

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