I think it's the default, which is 5. Everything about this system screams default. The RR database data is probably based on a mix of reports from scanner users and DSD+ users. Scanners don't seem to report the correct values, so I'd expect there to be some issues.
DSD+ correctly reports 422.2625 as site 1.7, but the DB has it as 1.6, so I guess that one came from a scanner user.