SCF

Business

Staffing Capacity Forecast Calculator

Retain the opening team under attrition, add planned hires, compound demand, and compare monthly capacity with required headcount.

Current productive headcountPlanned hires per monthAnnual attrition of opening team (%)Productive units per employee-monthStarting monthly demand unitsMonthly demand growth (%)Projection months

Opening team retained at horizon-

Gross planned hires-

Ending headcount reference-

Ending monthly productive capacity-

Ending monthly demand-

Capacity minus demand at horizon-

Headcount required for ending demand-

Ending reference minus required headcount-

Decision view

Staffing capacity and demand forecast

Staffing capacity and demand forecastUnits per month and people occupy separate panels on the same projection-month axis.

Exact scenario comparisonPlanned hires per month changes while all other entered assumptions remain constant.

Planned hires per month	Opening team retained at horizon	Gross planned hires	Ending headcount reference	Ending monthly productive capacity	Ending monthly demand	Capacity minus demand at horizon	Headcount required for ending demand	Ending reference minus required headcount

Period-by-period detail

Monthly staffing capacity and demand forecast

Each month recalculates retained opening headcount, gross hires, capacity, compounded demand, and exact headcount gap.

How to use Staffing Capacity Forecast Calculator

Enter opening headcount, hires, attrition, and productivity.
Enter starting demand, growth, and horizon.
Inspect capacity-demand and headcount curves together.

Calculator guide

Understanding Staffing Capacity Forecast Calculator

Staffing adequacy depends on two moving curves: available headcount/capacity and compounded demand/required headcount.

Retain the opening team Attrition is applied only to the opening team in this model.

Add planned hires New hires are added without their own attrition or ramp.

Calculate ending capacity Every reference employee uses the same entered productivity.

Compound ending demand Month 1 is the starting demand, so seventeen growth steps occur.

Calculation method

How the calculation works

Retain the opening team under one attrition assumption, add explicit gross hires, compound demand, and compare ending capacity with required headcount. Compound retention on opening headcount, add gross hires, multiply by productivity, and divide demand by productivity for required headcount.

Detailed calculation process

Forecast staffing capacity against compounded demand

The default starts with 24 people, hires 1.5/month, applies 15% annual attrition to the opening team, uses 160 units/employee-month, starts at 3,600 units, grows demand 2% monthly, and projects 18 months.

General formula: R_N = H_0(1-a/1200)^NH_add = hNH_N = R_N+H_addCap_N = H_N pD_N = D_1(1+g/100)^(N-1)H_req = D_N/pGap_H = H_N-H_req Opening-team retention compounds monthly, while planned hires add linearly. Demand compounds from month 1, and productivity converts both headcount and demand to comparable capacity.

What each symbol means

H_0, a Opening productive headcount and annual attrition (%).

N, h Projection months and gross hires/month.

R_N, H_add, H_N Retained opening team, added hires, and reference ending headcount.

p Productive units per employee-month.

D_1, g, D_N Starting demand, monthly growth (%), and ending demand (units/month).

Cap_N Ending productive capacity (units/month).

H_req, Gap_H Required headcount and reference-minus-required gap.

Worked substitution with the default inputs

1. Retain the opening team R_18 = 24(1-15/1200)^18R_18 = 19.1372 people Attrition is applied only to the opening team in this model.

2. Add planned hires H_add = 1.5(18) = 27H_18 = 19.1372+27 = 46.1372 people New hires are added without their own attrition or ramp.

3. Calculate ending capacity Cap_18 = 46.1372(160)Cap_18 = 7,381.957 units/month Every reference employee uses the same entered productivity.

4. Compound ending demand D_18 = 3,600(1.02)^(18-1)D_18 = 5,040.869 units/month Month 1 is the starting demand, so seventeen growth steps occur.

5. Reconcile required headcount H_req = 5,040.869/160 = 31.5054Gap_H = 46.1372-31.5054 = 14.6318Gap_units = 7,381.957-5,040.869 = 2,341.088 Headcount and unit gaps express the same modeled surplus.

The default ends with 46.137 reference headcount versus 31.505 required, a modeled capacity surplus of 2,341.088 units/month.

Purpose-built visual

Staffing capacity-demand forecast

A dual-panel forecast keeps units/month and people on separate axes while sharing the month timeline.

Live The chart is regenerated from current inputs.

Units Every axis, marker, and endpoint retains its stated unit.

Check The chart reconciles to the displayed calculation.

Worked situations

Practical examples

The default starts with 24 people, hires 1.5/month, applies 15% annual attrition to the opening team, uses 160 units/employee-month, starts at 3,600 units, grows demand 2% monthly, and projects 18 months.
The default ends with 46.137 reference headcount versus 31.505 required, a modeled capacity surplus of 2,341.088 units/month.

Better inputs

Useful tips

Change one input at a time and confirm both the result and visual move.
Keep the units stated beside every field.
Retain intermediate precision and round only the reported result.

Before relying on the result

Limitations and common mistakes

Hire timing within a month, ramp, skill mix, overtime, and attrition among new hires are excluded.
Productivity is held constant.
The model is not a service-level or queueing simulation.

Reference

Key terms

Reference headcount: Retained opening team plus gross planned hires.
Required headcount: Modeled demand divided by entered productivity.
Capacity gap: Reference capacity minus modeled demand.

Important note

Calculated from the entered values using the displayed accounting method. Reconcile material decisions with source records and applicable accounting policy.

Frequently asked questions

Does attrition apply to new hires?

No, not in this model.

Why use N minus one for demand?

Month 1 is the entered starting demand.

Can headcount be fractional?

Yes as a planning reference.

Does surplus guarantee service levels?

No.