As of yesterday's release, we can use rolling date ranges in segments - hurray!
However... we can only indirectly use rolling date ranges in calculated metrics (via segments).
So in order to create some really useful calculated metrics, we have to create (and manage) segments that duplicate the all the date ranges want to use - which seems like a waste of time and clutters the interface
e.g. we now have a date range of 'last month', and a duplicate segment of 'last month' for the sole purpose of use in calculated metrics
Any plans to allow us to use rolling date ranges directly in calculated metrics? :-)