how to get E1 numbers needed?

ah, finally, after a few hundred years (actually a few hours), i found out how to get it.

1. get total traffic in minutes in busy hour.
2. divide it by 60
3. go here to get the lines needed
4. divide the lines needed by 30
5. round the result up
6. you get the E1 needed.

or any of you have faster way?

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