---
name: headcount-scenario-modeler
description: "Builds 3-5 headcount scenarios (base, aggressive growth, conservative, downside, and a custom case) projecting monthly or quarterly headcount, hiring plans, attrition-adjusted net additions, and fully-loaded cost across a planning horizon, with sensitivity flags and a recommended scenario. Use when modeling workforce growth or reduction, stress-testing a hiring plan against revenue targets, or preparing headcount scenarios for board, finance, or leadership review."
argument-hint: "[growth-targets] [current-headcount]"
allowed-tools: ["Read"]
---

# Headcount Scenario Modeler

## Purpose
Generate multiple headcount scenarios — from aggressive growth to downside contraction — that translate business assumptions (revenue targets, attrition, hiring capacity) into month-by-month or quarter-by-quarter headcount and cost projections, so workforce and finance partners can pressure-test a plan before committing budget and headcount requisitions.

## When to Use
Invoke this skill when the user asks to:
- Model headcount growth scenarios tied to revenue or business targets
- Build a hiring plan and see its cost implications across a planning horizon
- Stress-test a workforce plan against different attrition or growth assumptions
- Prepare headcount and cost scenarios for a board deck, annual plan, or budget review
- Compare an aggressive vs. conservative hiring pace side by side
- Model a headcount reduction or hiring freeze and its cost/timeline impact

## Inputs Required
Before starting, collect:
- **Current headcount**: Total, and by department or function if available
- **Planning horizon**: How far out to model (e.g., 12 months, 4 quarters, 2 years) and interval (monthly or quarterly)
- **Business growth targets**: Revenue, ARR, or output targets driving the plan, with the ratio linking headcount to output if known (e.g., revenue per employee)
- **Attrition rate**: Annualized voluntary + involuntary attrition (blended, or by function)
- **Hiring capacity**: Realistic hires-per-period the recruiting function can execute, plus average time-to-fill
- **Fully-loaded cost per role**: Average total cost per headcount (salary + benefits + taxes + overhead), by level or function if available
- **Constraints**: Budget ceiling, hiring freeze dates, mandated ratios (e.g., IC-to-manager), or headcount caps

If cost per role is missing, assume a fully-loaded multiplier of 1.3-1.4x base salary and state the assumption. If revenue-per-employee is missing, derive it from current headcount and current revenue.

## Instructions

### Step 1: Establish the Baseline and Assumption Set
Lock the starting position before projecting forward.
- State current headcount and the ending point implied by each input assumption
- Convert annualized attrition to a per-period rate (annual rate ÷ periods; e.g., 18% annual ≈ 1.5%/month)
- Confirm the headcount-to-output driver: derive target ending headcount from growth targets ÷ revenue-per-employee, OR use explicit hiring targets if provided
- List every assumption in a single visible block so scenarios differ only by the levers being flexed

### Step 2: Build the Core Projection Mechanics
Every scenario runs the same period-over-period math:
- **Beginning headcount** (period N) = ending headcount (period N-1)
- **Attrition losses** = beginning headcount × per-period attrition rate (round to whole people)
- **Gross hires** = per-period hiring target, capped by recruiting capacity and time-to-fill lag
- **Net change** = gross hires − attrition losses
- **Ending headcount** = beginning + net change
- **Period cost** = average ending headcount × per-period fully-loaded cost, with new-hire cost prorated by start timing

Carry a running **backfill vs. growth split** so the reader sees how much hiring merely replaces attrition versus adds net capacity.

### Step 3: Generate 4 Scenarios (plus 1 custom slot)

**Scenario A — Base Case**
The most likely path. Uses the stated attrition, realistic hiring pace, and growth target as given.
- This is the recommendation baseline; every other scenario is a deviation from it

**Scenario B — Aggressive Growth**
Hiring accelerated to hit or beat the top-end growth target.
- Flex hiring pace up toward or past recruiting capacity
- Flag where hiring pace exceeds realistic time-to-fill (the "can we actually recruit this fast?" risk)
- Show the incremental cost over Base and the revenue-per-employee dilution during ramp

**Scenario C — Conservative / Capacity-Constrained**
Hiring held to what recruiting can reliably execute, or budget will comfortably fund.
- Show the resulting gap to the growth target and how many periods it delays the target ending headcount
- Useful when the buyer suspects the aggressive plan is not operationally real

**Scenario D — Downside / Contraction**
Reduced or frozen hiring, elevated attrition, or an active reduction.
- Model a hiring freeze (gross hires = 0, headcount declines by attrition only) and/or an explicit RIF
- Show months-to-target-cost-reduction and the point at which output capacity is at risk

**Scenario E — Custom (only if a specific what-if is provided)**
Run the buyer's named question — e.g., "what if attrition jumps to 25%?" or "what if we freeze in Q3?" — using the same mechanics.

### Step 4: Sensitivity Analysis
Identify which assumption moves the outcome most.
- Flex attrition ±5 points and hiring pace ±25% on the Base Case; report the swing in ending headcount and total cost
- Name the single most sensitive lever (usually attrition or time-to-fill)
- Flag any scenario where hiring pace exceeds recruiting capacity, breaches the budget ceiling, or violates a stated ratio constraint

### Step 5: Recommendation
Name one scenario as the recommended plan.
- Justify against the growth target, budget ceiling, and recruiting realism — not just cost
- State the top 2 risks to the recommended plan and the leading indicator to watch for each (e.g., "if monthly attrition exceeds 2%, Base slips a quarter")
- Be opinionated; do not present all scenarios as equal.

## Output Format
- **Structure**: Assumption block → one projection table per scenario → sensitivity summary → recommendation
- **Length**: 800-1,200 words plus tables
- **Format**: Markdown tables for each scenario (columns: period, beginning HC, attrition, hires, net change, ending HC, period cost, cumulative cost); prose for assumptions, sensitivity, and recommendation
- **Sections**: Assumptions → Base Case → Aggressive Growth → Conservative → Downside → Custom (if applicable) → Sensitivity Analysis → Recommendation
- **Tone**: Finance-people partner — quantitative, plain-spoken, decision-oriented; every number traceable to a stated assumption

## Quality Checklist
Before delivering output, verify:
- [ ] Every scenario projects across the full stated horizon at the stated interval (count the periods)
- [ ] Attrition, hires, net change, and ending headcount reconcile within each period (beginning + hires − attrition = ending)
- [ ] All assumptions appear in one visible block, and any derived or defaulted assumption is labeled as such
- [ ] Aggressive and Conservative scenarios each show their gap (or surplus) versus the growth target
- [ ] Sensitivity analysis names the single most impactful lever with a quantified swing
- [ ] Exactly one scenario is recommended with 2 named risks and a leading indicator for each

## Notes
- Attrition is usually the most underestimated lever — a 5-point swing in attrition often costs more net hires than a full quarter of the hiring plan
- Keep the backfill-vs-growth split visible: leadership frequently mistakes gross hires for net capacity growth
- If the buyer provides no revenue-per-employee ratio and no explicit hiring targets, the model cannot tie headcount to growth — ask for one before proceeding
- Whole-person rounding compounds over long horizons; note when fractional headcount is being rounded so cumulative totals stay defensible

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## How to use this skill

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**Installing in Claude Code:**
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Restart Claude Code or open a new session to register.

**Using in Claude.ai, ChatGPT, Gemini, or other AI tools:**

1. Drag this file into a new chat, or copy and paste its contents
2. Send your task or request as your next message — the AI will apply the skill where it fits

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