Documentation/How Tos/Calc: TRIMMEAN function

TRIMMEAN

Returns the mean of a set of numbers, ignoring a proportion of high and low values.

Syntax:

TRIMMEAN(numberlist; fraction)

numberlist is a range or array of numbers, not necessarily in order. TRIMMEAN returns the mean, ignoring a fraction (0 <= fraction < 1) of the outermost values in numberlist.

Specifically, where n is the count of numbers in numberlist, the highest and lowest INT(n * fraction / 2) values are ignored.

Example:

TRIMMEAN(A1:A100; 0.1)

returns the mean of the values in cells A1:A100, ignoring the lowest 5 values and the highest 5 values.