How "time elapsed" is calculated?

I think SCP calculates "time elapsed" including the time the request was closed (if it was reopened after that):

If a request was received on 10AM and closed on 11AM (same day), that is 1 hour of elapsed time. But if contact responds (re-opens the same request) on 4PM (same day) and we close on 5PM (same day), so system shows "Elapsed time" 7 hours (not 2 hours). And that is absolutely wrong. We can't use Elapsed time in our Reporting/measuring of our performance because of this.

Do you need a specific example?

Another question, how could I take a report, calculating only time spent in particular Status?

For example, we have additional Status, called "Coordinating" (that means we need additional help from our people outside SCP). Timer is not stopped, so I'd like to calculate how much time we spend in this status "Coordinating", eliminating statuses "Open" and others, that is how much time per product/group/etc. we spend on "outside SCP" coordination.