Data Dominance Factor
If any company in a sample accounts for more than 25 percent of the employees for a benchmark job, that company’s number of employees will be reduced for purposes of calculating averages and percentiles to a number that does not exceed 25 percent of the total employees reported to the job.
After determining the number of incumbents that can be retained, we count out from the median value (alternating higher and lower) to that figure and then discard those outside that limit. This ensures that data trimming supports retention of median values in every sample of company data in database results.