Average Annual Salary of a Cosmetologist. As of 2008 the median salary for a cosmetologist in the United States was $11.13, which includes tips and commission. The lower 10th percentile earned on average $7.47 hourly, while the upper 90th percentile earned a median salary of $20.41 hourly.verage Annual Salary of a Cosmetologist. As of 2008 the median salary for a cosmetologist in the United States was $11.13, which includes tips and commission. The lower 10th percentile earned on average $7.47 hourly, while the upper 90th percentile earned a median salary of $20.41 hourly.
The median is the ((n + 1)/2)th item, where n is the number of values. For example, for the list {1, 2, 5, 7, 8}, we have n = 5, so the median is the ((5 + 1)/2)th item.
One type of average, found by arranging the values in order and then selecting the one in the middle. If the total number of values in the sample is even, then the median is the mean of the two middle numbers. The median is a useful number in cases where the distribution has very large extreme values which would otherwise skew the data.