Excel 2010 :: Counting Users Per Hour For Each Hour

I work in a computer lab and we have to keep track of how many people sign in (using excel 2010), and how long they were here.

I'm looking for a way to count how many entries were made per hour for every hour someone was signed in.

For example someone signs in at 9:22 am and leaves at 3:34 pm.They were here from 9-10, 10-11, 11-12 etc.. and its getting very tiresome to go through and manually enter a "1" for each individual hour in each cell under the hour.

Is there a way I can feed the in and out times into a spreadsheet and have it automatically count how many people were in the lab each hour?

A
B
C
D
E

1
2
4
2

2
In
Out
8 am
9 am
10 am

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