Staff turnover: formula, example and benchmarks
Employee Turnover is the share of employees who left the company during a period. The metric reflects employer attractiveness and the quality of onboarding, management, and compensation, and it directly affects productivity, hiring costs, and service quality.
What the metric measures
Staff losses broken down into voluntary and involuntary attrition, regrettable and non-regrettable attrition, as well as early attrition (the first 30/90 days). It is useful to distinguish between permanent and contract staff, and full-time and part-time employment (FTE).
Calculation
- Turnover, % = Separations during the period / Average headcount × 100
where Average headcount = (Headcount at start + Headcount at end) / 2 - Voluntary / Involuntary, % — calculated separately by type of separation
- Regrettable, % = Separations of key/high-performing employees / All separations × 100
- Early Attrition (90d), % = Separations within the first 90 days / Hires during the period × 100
- Retention Rate, % = Employees remaining at the end of the period / Headcount at start × 100
- 12M Rolling Turnover — a 12-month rolling metric to smooth out seasonality
Define a policy: who is included in the base (FTE, part-timers, interns), the reference date (last working day), and whether internal transfers/rotations are included.
Calculation example
Average headcount for the year is 120 and 30 people left, 22 of them voluntarily. Turnover = 30 / 120 × 100 = 25% a year, voluntary turnover 18.3%. If 12 of the leavers had worked less than three months, the problem lies mainly in hiring and onboarding.
Data sources
HRIS/HR records, ATS (hiring), LMS (onboarding/training), eNPS/engagement surveys, exit-interview surveys, timesheets/productivity data, compensation data.
Interpretation
- Turnover↑ — risk of losing expertise, rising time-to-fill and replacement costs, declining productivity/service
- Voluntary↑ — problems with compensation, development, culture, workload, or management
- Early Attrition↑ — weak recruiting/onboarding, mismatched expectations
- Regrettable↑ — review your offers for key talent (career paths, RSUs/bonuses, hybrid/remote)
Useful breakdowns
- Department/team/location; manager; project/technology
- Job level (junior/middle/senior), critical roles
- Length of service (tenure) and hiring cohorts; work format (office/hybrid/remote)
- Reasons for leaving (compensation, leadership, development, workload, relocation)
Dashboard visualizations
- Trends in Turnover%, Voluntary/Involuntary, Early Attrition
- Cohort retention analysis by month of hire (survival curves)
- Heatmap of turnover by team/manager/location
- Pareto chart of reasons for leaving; correlations with eNPS/engagement/compensation
- Relationship between turnover and time-to-fill, hiring costs, and productivity
How to set targets
Set target ranges based on the market/roles, with separate KPIs for early and regrettable turnover. Action plan: adjust compensation and grades, build career paths, mentoring, flexible work formats, retention programs for key employees, and improve recruiting and onboarding.
Common mistakes
- Counting only total attrition without splitting it into voluntary/involuntary/early/regrettable
- Incorrect base (no contractor/FTE normalization), mixed periods
- Ignoring cohorts and tenure; focusing on the percentage without accounting for role criticality
- Lack of qualitative data from exit interviews and eNPS
Questions for discussion
- Which 3 reasons account for 80% of voluntary separations in key roles?
- How will turnover change after adjusting compensation/grades or introducing flexible work formats?
- Is onboarding effective: what is happening with early attrition in the first 90 days?
- What is the retention plan for high performers and at-risk teams?