When generating a report for a queue, the 'Opened' result only accounts for tickets that were opened during that span. Not for tickets that were open before the start of the span (a/k/a: Backlog). This makes it look like when you query for JPMorgan's 'Open' tickets from August 1st 2008 to August 4th 2008 that there are:
3 open tickets
and
592 closed tickets

I think the 'open' statement should probably be something like a UNION of Backlog tickets and the tickets that were open during the span in question:

and the 'Closed' statement should just limit the 'closed' period to the time in question... (instead of looking at when the ticket was opened in the queue)