Staffing Requirement Calculations

Use the Staffing Requirement Calculation feature in Workforce Management (WFM) to ensure you have the right number of agents to meet your service goals.

This section describes the key factors that affect staffing levels and helps you plan more effectively.

ASA and SLA Sensitivity

  • ASA (Average Speed of Answer): The average time it takes for a contact to be answered.

  • SLA (Service Level Agreement): The percentage of contacts answered within a defined threshold.

  • Stricter targets → More staff needed.

  • Relaxed targets → Fewer staff needed.

For example:

Service Target

Required fte
SLA=80% in 20 sec, ASA=30 sec 100
SLA=90% in 15 sec, ASA=20 sec 120

Note: The values shown above are for illustration only. Actual values may vary in real time.

If your staffing spikes unexpectedly, check whether the service targets were recently tightened.

Understaffing and Overstaffing Impact

  • Understaffing: Too few agents → Poor SL and ASA, higher occupancy.

  • Overstaffing: Too many agents → Better SL/ASA but low occupancy and higher costs.

For example:

Staffing level

sl (%)

asa (SEC)

Occupancy (%)
-15% Staffing 70 50 95
Optimal Staffing 85 30 85
+15% Staffing 92 20 70

Note: The values shown above are for illustration only. Actual values may vary in real time.

Always review occupancy together with Staffing Level (SL) to help prevent overstaffing.

Single vs Multiple Service Target Calculations

You can run staffing based on:

  • Single target: SLA, ASA, or Max Occupancy alone.

  • Multiple targets: A combination (e.g., SLA + ASA + Max Occupancy + Shrinkage).

For example:

Target combination

required fte
SLA Only 100
SLA+ASA 105
SLA+ASA+Max Occupancy+Shrinkage 110

Note: The values shown above are for illustration only. Actual values may vary in real time.

If staffing seems too high, check which combination of targets is active. The most restrictive target determines the result.

Shrinkage Sensitivity

Shrinkage accounts for time agents are unavailable due to breaks, meetings, training, or leave.

Example Calculation: Final Staffing = Base FTE / (1- Shrinkage)

Shrinkage (%)

Base fte

Final FTE
20 100 125
30 100 143

Note: The values shown above are for illustration only. Actual values may vary in real time.

Plan your shrinkage realistically. If it's too low, you may end up under-resourced.

Forecast Volume Sensitivity

Staffing scales with forecasted contact volumes.

More contacts → More staff.

Fewer contacts → Fewer staff.

For example:

Forecast Volume

Required fte
10,000 contacts 100
15,000 contacts 150

Note: The values shown above are for illustration only. Actual values may vary in real time.

Always ensure forecasts are up to date before running staffing.

Combined Factors Impact

Often, several factors change at the same time—for example, increased volume, tighter service level agreements (SLAs), and higher shrinkage.

The staffing engine calculates requirements based on all active parameters.

For example,

If volume rises by 20%, SLA is tightened, and shrinkage increases:

  • Required staffing can increase significantly (For example, from 100 FTE to 140 FTE).

Change one parameter at a time to clearly see its impact.

Agent Ready Time

Agent Ready Time is the time agents spend in a ready state, available but waiting for the next contact. The staffing simulation incorporates agent Ready Time into the calculation, so requirement numbers account for idle time between contacts and more accurately reflect how the contact center operates.

The calculation also uses configured skill groups and agent proficiency, which improves accuracy in multi-skill environments. Because the simulation follows a more realistic handling model, the required agent counts are typically higher than when only workload is considered.

For example:

Simulation mode

Required fte
Without agent Ready Time 100
With agent Ready Time considered 115

Note: The values shown above are for illustration only. Actual values depend on your configuration and traffic patterns.

If staffing must be recalculated after changes:

  • If schedules are already published, rerun Staffing for the active job.

  • If schedules are not yet published, update the existing job or run a new job, then rerun Staffing.

Until you recalculate staffing, existing jobs continue to show the previous requirement values.

Glossary

  • ASA (Average Speed of Answer): Average time to answer a contact.

  • Agent Ready Time: The time an agent spends in a ready state, available but waiting for the next contact.

  • SLA (Service Level Agreement): Target percentage of contacts answered within a set time.

  • FTE (Full-Time Equivalent): Number of full-time staff required.

  • Shrinkage: Percentage of time agents are unavailable.

  • Occupancy: Percentage of logged-in time agents spend handling contacts.

Summary Table - How Each Factor Affects Staffing

Factors

higher value effect

Lower value effect
SLA / ASA More FTE Fewer FTE
Shrinkage More FTE Fewer FTE
Forecast Volume More FTE Fewer FTE
Skill Priority More FTE to that skill Less FTE to that skill
Occupancy Target Fewer FTE More FTE
Agent Ready Time More FTE Fewer FTE