by Paul Leamon, Director of TotalView Marketing

The introduction of skills-based routing features for Automated Call Distributors (ACDs) has given call center managers very powerful capabilities to route incoming calls to the available agent most skilled to handle each call. However, today's call center management systems have not entirely caught up to this new technology. As a result, scheduling and managing a call center with skills-based routing can be a challenge.

Although skills-based routing can be defined in a number of ways, the broadest definition is: Skills-Based Routing: A call center term for routing incoming calls based on the type of service requested, assuring that calls go to agents with the skills to provide the highest quality of service to the calling customer. Using this definition, call routing is first examined without considering agent skills. Next, the various possible combinations are explored when skills-based routing is considered. Finally, the factors needed to manage a call center using skills-based routing are described.

Traditional ACD Call Queuing
Traditional ACD call queuing maps each call type to a single queue served by a single agent group, as shown in Figure 1. Since multiple agent skills are not considered, each agent handles only a single type of call.
 

Skills-Based Routing with Multiple Agent Groups
Some ACDs provide skills-based routing by allowing an agent to belong to more than one agent group simultaneously.

• Sales Agents with only sales skills belong to the sales agent group.

• Service Agents with only service skills belong to the service agent group.

• Agents with both Sales and Service skills belong to the sales and service agent group.

Skills-Based Routing with User Defined Rules
Another way ACDs can provide skills-based routing is through user defined rules, which allow each call type to be queued to different groups of agents (or skills). These rules can be based on conditions such as time in the queue, number of available agents in an agent group (or with the same skill) and time of day. Some ACDs also allow calls to be queued to multiple agent groups (or skills) at one time.

Complex Skills-Based Routing
Providing the ultimate control and flexibility, some ACDs allow all the previous routing features to be used together.

For simplicity, all diagrams have only shown two call types requiring only two different agent skills. Call centers could have 30 or more call types and agent skills. This magnifies the complexity and creates a real challenge for call center management.

Are We Done?

There are several questions that must be answered when scheduling agents in a skills-based routing call center. The first and foremost question is "Are we done?" This question is the heart of the problem when developing schedules for agents with multiple skills. That is, how does a call center manager know when the right schedules have been created to meet the service level goal for each call type?

Traditional ACD call queuing in Figure 1 allows straightforward planning and agent scheduling. An Erlang C formula calculates the number of agents needed to handle forecasted call volumes and handling times to provide a certain level of service for each quarter or half-hour throughout the day. Once this is done, schedules can be created for the number of agents needed in each agent group. Creating schedules is straightforward since each agent has a single skill. For each quarter or half-hour period that an agent is scheduled to handle calls, the agent counts toward the total number of agents needed for that call type. With traditional ACD call queuing, the task is complete when the agents scheduled matches the number of agents needed. However, the process is not as easy if calls are being routed to agents with multiple skills.

Skills-based routing can still use an Erlang C formula to calculate the number of agents needed for each call type. However, it is a complex task to determine if the total number of multi-skilled agents scheduled matches the number of agents needed for each call type. In order to determine a match, the amount of time each agent is expected to handle each call type for every quarter or half-hour interval during the day must be calculated. This analysis is not easily done, since a multi-skilled agent may spend anywhere from 0 percent to 100 percent of their time handling each call type. There are several factors in skills-based routing that can impact the amount of time an agent spends handling each call type and must be considered before answering the question, "Are we done?"

Agent Interdependency
A key aspect of the question, "Are we done?" is that the time each agent will spend handling each call type depends on the schedules and skill sets of all other agents. The effectiveness of an individual agent's schedule changes as other agents are added. Look at Figure 2 and assume that the Sales Agents (single skill) have not been scheduled. Without the Sales Agent group, the Sales and Service Agents (multi-skill) would handle sales calls 100 percent of the time. Now, suppose all the Sales Agents are scheduled. This change directly affects all Sales and Service Agents, who now would work 50 percent on sales calls and 50 percent on service calls. Therefore, the question, "Are we done?" must be evaluated each time an agent's schedule is added or changed.

Call Routing Rules
If an ACD provides user defined call routing rules, then the time each agent spends on each call type may be affected. For example, ACD call routing rules can cause difficulties if they are based on real-time events, such as time of day and/or day of week. Another common use of ACD rules is to protect small, specialized agent groups (skill groups) so they would be available for specialized calls. Suppose the Sales and Service Agents in Figure 4 could handle both Japanese and English calls. The rules for routing calls might send English calls to Japanese speaking agents only if there are three or more agents with the Japanese skill in an available state on the ACD. User defined rules such as these can have a major impact on the effectiveness of scheduling techniques in a multi-skill call center.

Multi-Skilled Agent Efficiencies
An interesting forecasting issue occurs with skills-based routing. The number of agents per call type calculated by an Erlang C formula does not consider large team efficiencies resulting from the use of multi-skilled agents. Because of the random arrival of calls, a combined group of 200 agents with Sales and Service Skills can handle more calls than one group of 100 agents with only the Sales Skills and another group of 100 agents with the Service Skills. Using an Erlang C formula to determine the number of agents needed in a multi-skill call center may result in scheduling more agents for each call type than actually needed.

Agent Preferences
Many call centers grant agents schedule preferences by seniority. This practice is affected when developing schedules for multi-skilled agents. For example, it may be most efficient or necessary to place senior agents (agents with the most skills) at the least popular time of the day (assuming junior agents have fewer skills). If breaks, lunch and/or entire schedules are traded to give senior agents their preferences, the coverage for all call types handled by these agents will change. In order to prevent coverage from changing, the option of trading breaks, lunches and/or schedules would be limited to agents who have the exact same set of skills. In addition, priorities must match exactly for ACDs that allow skills to be prioritized. Therefore, if unique skill sets are assigned to only a few agents, it becomes difficult for senior agents to obtain preferred schedules and still meet service level goals.

Specific Call Type Workstations
Call centers may have a limited number of special agent workstations that must be used for certain call types due to the associated software needed. This limitation introduces a new factor into the scheduling of multi-skilled agents. Even though an agent has a particular skill, it may not be used unless the agent is assigned to a special workstation. Agent schedules should also efficiently utilize special workstations without long idle periods. Since more agents may have the skill than the number of workstations, schedules must consider which agents are assigned to special workstations.

Intraday Management
Assuming the "Are you done?" question has been answered and efficient schedules have been created, managing changing conditions of a call center during the day is a challenge. For example, if several multi-skilled agents call in sick, how can management predict if service level goals for all call types are being met? What times of the day will be affected? If unusually high call volumes are being received for a particular call type, which multi-skilled agents should be offered overtime to increase the number of available agents? Skills-based routing makes intraday management of each call type even more complicated due to the interdependency of agents' schedules.