Difference of column values in Pivot table

[Qlik2019]

Dear All,

I am trying to show difference of column values in pivot table.

1. Unable to capture column values to show difference in table.

2. Hide specific column.

I have attached working file with explanation of intended result.

Here is example I have take 3 months but in actual months will increase have only 6 months.

Sheet Name: This sheet.

PFA file.