Finding out number of agents for an inbound call center can be quite complex task and sometimes involves not so simple maths. As discussed earlier, one should use queueing theory to estimate needed number of agents because the intuition sometimes tells us lower numbers than actually required.
For example, a single server system which need on average 5 minutes to serve one caller, will not be able to serve well even if the calls arrive in average with 5 minute and 15 seconds interval. The queue will grow due to fluctuations of real durations, queue will grow and after a while it will establish around 1 hour and 40 minutes. Let's see what will be a queue size for various other call arrival times:
| Serve time, 1/μ | Arrival interval, 1/λ | Queue wait time, t |
| 5 min | 5 min 15sec | 100 min |
| 5 min | 5 min 30sec | 50 min |
| 5 min | 6 min | 25 min |
| 5 min | 8 min | 8 min 20 sec |
| 5 min | 10 min | 5 min |
| 5 min | 20 min | 1 min 40 sec |
The results are quite surprising: even if the calls arrive with less frequency, the average wait time is considerable.
Of course, single server (agent) example is oversimplification - adding the second agent would cut waiting times significantly, because chances of two longer-than average calls arriving in same time are lower. However, it gives an idea of the complexity of the problem even at this small scale.
One of the ways of avoiding increasing number of agents and associated costs, is to offload some of the work to automation. There are many functions which can be effectively performed without involvement of live agent, and many callers do actually prefer interaction with automated system rather than with time-pressed agent who is eager to close the call (subscription, sale, etc) as fast as possible.
Here are just some of the example tasks automated IVRs can do without human intervention:
- Take orders (a.k.a. shopping carts), including payment processing;
- Information services (event and transportation schedules, product information, order status, weather information);
- Order or shipment status inquiry;
- Polls, surveys and voting.
See our IVR Builder Demo for more information on how to easily add advanced IVR service to an inbound Call Center in minutes.
