Coefficient Of Variation

Also known as Relative Standard Deviation (RSD).
The variance is the average of the square of the deviations
It is often necessary to compare the dispersion of two groups of vaues.
If the two groups have very different standard deviations
It is therefore much more relevant to look at the size of the standard deviation relative to the mean.
The coefficient of variation is just the standard deviation divided by the mean

CV = standard deviation / mean

This coefficient can then be multiplied by 100 to create a percentage.

When to Use

This coefficient is meaningful when you have positive values, ie a ratio scale
It is not meaningful for data on an interval scale