One report supplies the numbers here: SHRM's 2022 Human Capital Benchmarking Report. Four figures, and you need all four plus the ability to place an organization against them.
The 2022 distribution
- Average: 1.70 HR staff per 100 employees
- Median: 1.11
- 25th percentile: 0.42
- 75th percentile: 2.02
The average sits above the median because small organizations carry proportionally larger HR teams and pull the mean up. Expect the exam to ask for one of these by name and offer the other three. Average is 1.7, median is 1.11; that is the single most confused pairing in the unit. A "4.5 per 100" answer is a rule-of-thumb ceiling that verification did not support.
Placing an organization
Use the same formula: (HR FTEs / total FTEs) × 100.
Worked example: 400 FTEs with 3 HR FTEs. 3 / 400 = 0.0075, times 100 = 0.75 per 100. That is below the median of 1.11 and above the 25th percentile of 0.42. To land above 2.02 this employer would need far more HR staff; to fall under 0.42 it would need fewer than about 1.7 HR FTEs at that size.
What the benchmark is and is not
- The 2022 data were collected April through November 2021, with 945 responding organizations.
- It publishes a percentile distribution, not only an average.
- It sets no required minimum. Any answer claiming a required 1.5 per 100 is refuted.
- It is not total FTEs divided by HR FTEs. That inverts SHRM's formula.
Carry this: 0.42 / 1.11 / 1.70 / 2.02, and know which one is the average.