Syntax of TRIMMEAN function

TRIMMEAN(array, percent)

The TRIMMEAN function syntax has the following arguments:

• Array: The array or range of values to trim and average.
• Percent: The fractional number of data points to exclude from the calculation. For example, if percent = 0.2, 4 points are trimmed from a data set of 20 points (20 x 0.2): 2 from the top and 2 from the bottom of the set.

Explanation of TRIMMEAN function

• If percent < 0 or percent > 1, TRIMMEAN returns the #NUM! error value.
• TRIMMEAN rounds the number of excluded data points down to the nearest multiple of 2. If percent = 0.1, 10 percent of 30 data points equals 3 points. For symmetry, TRIMMEAN excludes a single value from the top and bottom of the data set.

Example of TRIMMEAN function

Steps to follow:

1. Open a new Excel worksheet.

2. Copy data in the following table below and paste it in cell A1

Note: For formulas to show results, select them, press F2 key on your keyboard and then press Enter.

You can adjust the column widths to see all the data, if need be.