The Excel SKEW.P Function

Related Function:
SKEW Function
Skewness

The Skew of a population is a measurement of the asymmetry of the distribution about the mean.

  • A skew of zero indicates perfect symmetry;
  • A positive skew indicates that more values lie below the mean;
  • A negative skew indicates that more values lie above the mean.
Examples of Positive and Negative Skewed Distributions
Positive Skew Negative Skew
For more information on skewness, see the Wikipedia Skewness page

Function Description

The Excel SKEW.P function calculates the skewness of the distribution of a supplied set of values.

Note: the Skew.P function was only introduced in Excel 2013 and so is not available in earlier versions of Excel.

The syntax of the function is:

SKEW.P( number1, [number2], ... )

Where the number arguments provide a minimum of 3 values that make up the data set. These can be individual numbers or arrays of numbers.


Skew.P Function Example

  A B
1 1  
2 1  
3 2  
4 2  
5 2  
6 2  
7 3  
8 3  
9 3  
10 4  
11 4  
12 5  
13 6  
14 7  
15 8  

Column A of the above spreadsheet on the right shows 15 data values. The distribution of these values is shown in the chart below:

Distribution of Points in Skew Function Example

The population skewness of the values in the spreadsheet can be calculated using the Excel Skew.P Function as follows:

=SKEW.P( A1:A15 )

This gives the result 0.774523929, indicating that the data set has a positive skew.


For further details and examples of the Excel Skew.P function, see the Microsoft Office website.


Skew.P Function Errors

If you get an error from the Excel Skew.P function this is likely to be one of the following:

Common Errors
#DIV/0! -

Occurs if either:

  • Fewer than 3 data values have been supplied to the function;
  • The standard deviation of the data points is zero.
#VALUE! -

Occurs if any of the supplied number arguments that are supplied directly to the function are not recognised as numeric values.

(Note that if the Skew.P function is provided with a reference to a range of cells, any text values within this cell range are simply ignored and do not cause the function to return an error).