How to edit macro for auto-fill?

I'm using 2 macros for auto-fill data and both work fine, but I have problem when I had only one row? Could you please give me some advise how to change these codes?

Thank you in advance!

Code 1

 
    Dim AF As Long
    AF = ActiveSheet.UsedRange.Rows.Count
    Range("et2").AutoFill Destination:=Range("et2:et" & AF)

Code 2

     ActiveCell.Offset(0, -1).Select
     Selection.End(xlDown).Select
     ActiveCell.Offset(0, 1).Select
     Range(Selection, Selection.End(xlUp)).Select
     Selection.FillDown