Thread: Macro to susbtract any 2 columns

I have a sheet which has columns (eg:- A to Z) with decimal values.
Column A could have 10 rows and Column B could have 100 rows.
The user wants an option of subtracting any 2 columns.
So, it means that the user will require a form which will have something like
Choose 1st column : say A
Choose 2nd column : say F
And then press button 'Substract'

It will give result in a column 'AA' as ColumnF- ColumnA for all the values in these columns, if data exists in either of the two.

Can someone please give me the VBA code to achieve this? Thanks

Sub calculate()
    Dim column1, column2, mesage1, mesage2
    Dim i As Long
     mesage1 = "Please input 1st column:"
     column1 = InputBox(mesage1)
     column1 = Val(column1)
     mesage2 = "Please input 2nd column:"
     column2 = InputBox(mesage2)
     column2 = Val(column2)
     For i = 2 To 200
        If Worksheets(1).Cells(i, column1).Value = "" And Worksheets(1).Cells(i, column2).Value = "" Then Exit Sub
        Worksheets(1).Cells(i, 27).Value = Worksheets(1).Cells(i, column2).Value - Worksheets(1).Cells(i, column1).Value
     Next i
     Range("A1").Select
End Sub

I add one row in code (after Dim i As Long):

Sub calculate()
    Dim column1, column2, mesage1, mesage2
    Dim i As Long
     Worksheets(1).Columns(27).ClearContents
     mesage1 = "Please input 1st column:"
     column1 = InputBox(mesage1)
     column1 = Val(column1)
     mesage2 = "Please input 2nd column:"
     column2 = InputBox(mesage2)
     column2 = Val(column2)
     For i = 2 To 200
        If Worksheets(1).Cells(i, column1).Value = "" And Worksheets(1).Cells(i, column2).Value = "" Then Exit Sub
        Worksheets(1).Cells(i, 27).Value = Worksheets(1).Cells(i, column2).Value - Worksheets(1).Cells(i, column1).Value
     Next i
     Range("A1").Select
End Sub

Many Thanks pera68. Why doesn't column AA show negative values? Plz help!

If value in column2 is less than value in column1 then results is negative number.
If you wish you change operator And into Or in line "If Worksheets(1).Cells(i,column1),value.... and results in column AA is blank.

TYVM for your patience.