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Employee Records

Part of HR reporting and workforce data

Comparing turnover rates using a clear time period

Compare employee turnover with matched exit definitions, populations, dates and denominators. Learn why public job mobility is a different measure.

Editorial responsibility: Cooper Anderson · · 2 min read

This is an editorial pen name used by the publication, not a claim of an independently verified personal identity. Original editorial credit: Desk People Systems.

Compare turnover rates only when the exit rule, employee population, period and denominator method are clear. State these beside each figure. A monthly rate and a yearly rate cover different lengths of time, and “turnover” may mean all exits or only voluntary resignations.

Decide which exits count

For how many people left the employer, count distinct people whose employment ended in the period. For voluntary resignation, record which exit categories qualify. An internal transfer may leave a team without exiting the employer; specify the boundary.

WGEA says its Workforce Management Statistics (WMS) collect numerical data on employee movements during the relevant 12-month reporting period. Its analysis includes resignation trends.

Match the period and denominator

One internal convention is defined exits during the period ÷ average headcount for the same period × 100. It is not a statutory or universal formula. Record how the average is calculated, such as from regular monthly snapshots, and use the same population rule in the numerator and denominator. Including casual employees in exits while excluding them from headcount would distort the rate.

For example, 12 defined exits over an illustrative 12-month period and an average headcount of 100 produce a rate of 12%. The calculation says nothing by itself about why people left. If a team was reorganised halfway through the year, mark that boundary change before comparing the result with another period.

ComparisonCheck first
One quarter against anotherExit categories, entity scope, headcount method and any difference in days covered
One month against a yearState each period; do not treat the raw percentages as equivalent exposure
One team against anotherTransfers, shared roles and small denominators
Internal rate against a public figureWhether events, population, period and denominator match

Turnover rate calculation example

  • 12Defined exits (-month period) — 12
  • 12%Turnover rate

Avoid a false benchmark

The Australian Bureau of Statistics publishes a national job mobility rate based on its Participation, Job Search and Mobility survey. It is a national survey measure, not one employer’s exits divided by average headcount. Its percentage is therefore not a direct benchmark for the internal rate above.

Record the start and end dates, extraction date and handling of exits entered late. Keep the definition stable when repeating the calculation; mark any break in the series. For a small team, show the exit count with the percentage so readers can see the effect of a single departure.

Use the rate to decide what to investigate. It does not establish an employee’s reason for leaving or prove that a manager caused the change.

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