Finding difference two columns untill empty cells encountered

This piece of code will find difference between two column until it finds empty cell.




Sheets("Collateral Type Codes").Select
Sheets("Collateral Type Codes").Cells(3, 7).Value = "Difference"
For i = 4 To 100000
If IsEmpty(Sheets("Collateral Type Codes").Cells(i, 2)) Then
GoTo Label2
End If
Sheets("Collateral Type Codes").Cells(i, 7).Value = Sheets("Collateral Type Codes").Cells(i, 3).Value - Sheets("Collateral Type Codes").Cells(i, 4).Value
Next i
Label2:
ActiveSheet.Range("G3").Select
    Selection.AutoFilter
    ActiveSheet.Columns("D:D").AutoFilter Field:=1, Criteria1:="<>0", Operator:=xlFilterValues