In the following CSV, I need to append new row values for it. ID date balance 01 31/01/2021 100 01 28/02/2021 200 01 31/03/2021 200 01 30/04/2021 200 01 31/05/2021 500 01 30/06/2021 600 Expected output: ID date balance 01 31/01/2021 100 01 28/02/2021 200 01 31/03/2021 200 01 30/04/2021 200 01 31/05/2021 500 01 30/06/2021 600 01 30/07/2021 999