[otrs] Stats about escalations

Hi, I'm trying to find out a way to generate a report of the escalation that have occured in the last month. I've managed to get different information on tickets from the tickets table, but I don't see any fields that would let me know if the ticket has been escalated. There are a few fields starting with 'escalation', but according to my tests, they are fields that define when the ticket will be escalated, while I'm looking for a way to see if an escalation has occured. The other fields that look interesting are: - timeout - until_time but I can't figure out their use. Any help would be appreciated. Thanks, Ugo