Yes. These fields needs to capture the data in reporting as well.
It does seem they are dynamically calculated. I ran a "Incidents with Incident Service Targets" report and both the "Time Remaining" and "Elapsed Time" fields were all blank.
I don't know the exact formula that Remedyforce uses to compute the values, but their calculations undoubtedly take into consideration the Business Hours setup in your org.
I believe you would need to write some Apex code to simulate the same calculations, and it may or may not be trivial in nature. You will need to look up via SOQL/Apex the Business Hours object and use the diff method.
Here's some links and sample code to point in that direction if you choose to pursue this route (apologies if the formatting doesn't carry over):
BusinessHours bh = [SELECT id, name, isactive, isdefault, MondayStartTime, MondayEndTime, TuesdayStartTime, TuesdayEndTime /* ... */ FROM BusinessHours WHERE isdefault = true LIMIT 1];
DateTime startDate = DateTime.newInstance(2014, 7, 8, 7, 0, 0);
DateTime endDate = DateTime.newInstance(2014, 7, 9, 7, 0, 0);
// This example prints the milliseconds representing the number of
// business hours that elapse between the start and end dates.
// In this example, the actual clock time between start and end is 24 hours,
// but in my org with 8am-5pm business hours schedule, this returns
// 32400000 milliseconds (9 hours).
System.debug( BusinessHours.diff( bh.id, startDate, endDate ) );
Thanks for your suggestions Doug Ayers. I Voted for this Idea.
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