You do not care what the utilization is outside of business hours, so simply exclude all data in that period from your consideration; don't even use it for comparison.
What is the 95th percentile during business hours?
(it will take some SQL to write a report for this)
Adding to what RichardLetts was saying, i often use SQL to create reports for people that give, for example, the percent of business hours where interface utilization is above a threshold value like 90% of capacity, and then add in some charts that show the utilization rates over time so it is easy to see if the higher utilization periods come along with any recognizable trends that might be able to tweak. Are we always maxing it out at 9 am when staff are all logging into their VDI? Is there a report that gets pushed out at 2 pm every Thursday triggering the bandwidth contention? If you don't know SQL you can do this using the Orion web report interface by just setting up the criteria in the data source similarly to this example. (my screenshot is from the NPM 12 RC, yours may differ slightly)
Hope that helps
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