The maximum physical attendee capacity of an [Event](http://schema.org/Event) whose [eventAttendanceMode](http://schema.org/eventAttendanceMode) is [OfflineEventAttendanceMode](http://schema.org/OfflineEventAttendanceMode) (or the offline aspects, in the case of a [MixedEventAttendanceMode](http://schema.org/MixedEventAttendanceMode)).