Macro - Create / Copy / Paste Formula every 5 rows for varying range

I don't know if you want to delete the empty rows but if you do you could add this to the code.
Make sure you try it on a copy of your workbook in case it is not what you want.

Range("L1:L" & lr).SpecialCells(4).EntireRow.Delete

Put this line between "Next i" and "End Sub"