Dashboard Analytics Duration

[Sheila Gwido]

Hello!
When I download dashboard analytics at the end of the meeting I get some values that I don't understand:

Join            Left            Duration
17/1/2023 08:56:18    17/1/2023 14:02:36    05:04:30  -OK
17/1/2023 09:00:18    17/1/2023 14:01:22    05:00:32  -OK
17/1/2023 08:56:18    17/1/2023 14:02:16    05:05:51  -OK
17/1/2023 08:56:29    17/1/2023 14:02:36    04:31:21  -Missed 30min?
17/1/2023 08:56:16    17/1/2023 14:02:26    05:06:10  -OK
17/1/2023 08:58:10    17/1/2023 14:02:46    05:04:14  -OK
17/1/2023 09:10:30    17/1/2023 14:02:16    04:18:40  -Missed 40min?

Is the duration column the difference between join and left time of each user?
Anyone can explain me what is duration?
Trying to guess by myself I think this is the code involved in this data: https://github.com/bigbluebutton/bigbluebutton/blob/7b5a02e91d2bfc304141e36e4f515354c7a84a6b/bbb-learning-dashboard/src/components/UserDetails/component.jsx (line 63)
But I'm no able to understand it.
Thanks!!