attrition rate

An attrition rate looks like a simple figure and is surprisingly easy to calculate three different ways.

The denominator is where it goes wrong. Headcount at the start of the period, headcount at the end, and average headcount across it all give different results, and the difference is largest in exactly the organisations that are growing or shrinking fastest.

Average headcount across the period is generally the sounder choice, because it reflects the population actually at risk of leaving.

Two other decisions need stating. Whether casuals are included, which can move the figure dramatically. And whether internal transfers count as departures, which they should not.

Write the definition down. A rate nobody can reproduce is not a measure, it is an opinion with a decimal point.

The Fair Work Ombudsman covers employee records. This is general information rather than legal advice, and obligations vary by state and territory.

See Sentrient’s HR management system and employee management system.