Disk volume Usage (Percentage vs real volume)

The majority of the alerts we get every day are high volume usage and sometimes its hard to work with this because you don't know how large the volume is. For example, working on a 50TB system and your threshold is set at 90% you will begin to receive alerts when you still have 5 TB left. Would it be possible to have a feature that would allow you to see the size of the drive and set the alert for GB instead of percentage? This would allow for faster use of thresholds on drive alerts.