Calculate attrition rate from employees who left and average or start and end headcount, with an optional annualized rate, or solve for departures.

Use departures and headcount from the same reporting period.

Often (start headcount + end headcount) ÷ 2 for the period.

Annualize
Optional. Adds an annualized rate: period rate × 12 ÷ months.

Attrition Formula

The following formula can be used to calculate the attrition of a business.

A = EL / AE × 100
  • Where A is the attrition rate (%)
  • EL is the total number of employees that have left
  • AE is the total average number of employees

To calculate an attrition rate, divide the number of employees that have left by the average number of employees, then multiply by 100.

Attrition Definition

Here, attrition means departures divided by average headcount for the same period. Use a consistent definition of departures; the ratio does not distinguish replaced from unfilled roles. Rates can exceed 100% when repeated hiring and departures occur. Expected departures may be fractional planning estimates, while observed counts are whole people.

Attrition Example

How to calculate attrition?

  1. First, determine the number of employees that left the company.

    Determine the total number of employees that left a company during a certain time period.

  2. Next, determine the total average number of employees.

    Determine the average number of employees during the same time period.

  3. Finally, calculate the attrition.

    Calculate the attrition using the formula above.

FAQ

What is attrition?

Attrition is a measure of the rate at which employees leave the employment of a company.

Attrition Calculator screenshot