What is Erlang C?

Erlang C is a mathematical formula used to calculate the required number of agents in a contact center to handle incoming calls while maintaining a specified service level. It helps workforce planners determine the optimal staffing needed to manage call volumes efficiently, minimizing customer wait times and ensuring agent productivity.

Why Use Erlang C in Contact Centers?

Contact centers experience fluctuating call volumes throughout the day. Overstaffing leads to unnecessary costs, while understaffing results in poor customer experience and long wait times. Erlang C provides a scientific approach to forecasting and scheduling, ensuring:

• Adequate staffing to meet demand.
• Improved customer satisfaction.
• Better resource utilization.
• Achievement of service level targets.

How Erlang C Works

Erlang C calculates the probability of calls waiting in a queue based on three primary inputs:

1. Call Volume – Number of calls expected within a specific period.
2. Average Handling Time (AHT) – The time taken to handle each call, including talk and wrap-up time.
3. Number of Agents – The number of available agents to manage calls.

The formula considers these factors to estimate:

• Average wait time for calls.
• Percentage of calls answered within a specific timeframe (service level).
• Required agents to meet service level goals.

Key Benefits of Erlang C

• Accurate Forecasting: Predicts agent requirements with precision.
• Cost Optimization: Balances operational costs by preventing overstaffing.
• Service Level Management: Aligns workforce to meet defined performance targets.

Practical Example

Imagine a contact center expects 200 calls per hour, with each call taking an average of 3 minutes to handle. The goal is to ensure 80% of calls are answered within 20 seconds. Using Erlang C, planners can calculate the minimum number of agents required to achieve this service level.

Implementing Erlang C

To implement Erlang C in your contact center:

1. Gather historical call data.
2. Calculate call volumes and average handling time.
3. Use Erlang C calculators or workforce management software.
4. Adjust for shrinkage (breaks, training, etc.).
5. Continuously monitor and refine forecasts.

Tools and Software

Several tools and software solutions integrate Erlang C for contact centers, simplifying workforce planning and ensuring real-time adjustments.

Conclusion

Erlang C is a cornerstone of efficient workforce management in contact centers. By leveraging its calculations, businesses can enhance customer experience, optimize costs, and achieve consistent service levels. For tailored workforce planning solutions, contact us today!