 Also, there exist platykurtic densities with infinite peakedness,

and there exist leptokurtic densities that appear flat-topped,

For a sample of "n" values the sample excess kurtosis is

where "m"4 is the fourth sample moment about the mean, "m"2 is the second sample moment about the mean (that is, the sample variance), "x""i" is the "i"th value, and formula_23 is the sample mean.This formula has the simpler representation,

where the formula_25 values are the standardized data values using the standard deviation defined using "n" rather than "n" − 1 in the denominator.For example, suppose the data values are 0, 3, 4, 1, 2, 3, 0, 2, 1, 3, 2, 0, 2, 2, 3, 2, 5, 2, 3, 999.