Insert 5 rows starting from cell A5, then go to the next 20th row and insert 5 blank rows

Hi

I'm trying to start at cell A5
Insert 5 blank rows
Then count down 15 rows to cell A20
Insert another 5 rows
Then count another 15 rows so at cell A40 insert another 5 blank rows


Loop the same as above until the last row.

Thanks for the help
It works fine when there are no blank cells in column A

The problem is in column A I get a blank cell every 15 rows (so I need to insert 5 blank rows whenever cell in column A is blank