Hi

I'm looking to record the number of people in the building at any one time based on arrival and departure times. So if person 1 arrives at 07:55 and leaves at 17:00 and person two arrives at 09:00 and leaves at 16:30 I would be able to show that there was 1 person in the building until 09:00, then there were two until 16:30, then just one until 17:00.

I'm planning to do this with the data of 200-300 people on a 15 minute basis so it's not something I would want to do manually!

Thanks in advance.