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I leave my thoughts at the end.....
Question: Is there an effect on required FTE number for Email channel, if the SLA target get changed? For example, suppose current SLA target (for Email only) is 90% within 4 hours. Provided all other matrices such as volume, AHT, delay, occupancy, arrival pattern, shrinkage remain unchanged, will the FTE requirement go down if SLA target revised at 70%? How much will be the change? Can anybody assist to explain the relationship between SLA target and FTE headcount for email and if there is any standard formula?
Reply 1: Whenever my guys have planned emails we’ve based it on a carry forward calculation rather than service level, e.g. less than x percentage of work brought forward + input carried forward into the next day/week. By handling volumes that way I’ve always found the service level as such looks after itself.
-------------------------------My Views--------------------------------
Changing your Email Service Level should not, by itself, in the long run, change FTE requirements to meet the new service level target.
In its most basic form, the Productive FTE required for the email channel is predicated on "New Incoming + Maintaining Backlog Level Stability."
Because this is not a live channel, there is no need to load workload for any kind of Erlang unless your new Service Level target is close to live, i.e., less than 1 hour. Changing the Email Service Level will result in a short-term requirement increase or decrease (depending on whether you are increasing or decreasing the SLA target) while you get the backlog level balanced against the new Service Level Target, but otherwise required productive FTE requirements will return to the same levels once backlogs are balanced again.
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