Keeping backups for long periods of time can cause the N2WS database to grow and therefore affect the size you need to allocate for the CPM data volume. N2W Software estimates that every GiB will accommodate the backup of 10 instances. N2W Software estimates that 10 instances are correct when every record is kept for around 30 days. If you want to keep records for 90 days, triple the estimate, i.e., for 10 instances make the estimate 3 GiB, for 20 make the estimate 6 GiB, etc.