Returns the skewness of a distribution. Skewness characterizes the degree of asymmetry of a distribution around its mean. Positive skewness indicates a distribution with an asymmetric tail extending toward more positive values. Negative skewness indicates a distribution with an asymmetric tail extending toward more negative values.
Syntax:= SKEW(number1, [number2], …)
The SKEW function syntax has the following arguments:
 Number1, number2, … Number1 is required, subsequent numbers are optional. 1 to 255 arguments for which you want to calculate skewness. You can also use a single array or a reference to an array instead of arguments separated by commas.
Example: Let’s look at some Excel SKEW function examples and explore how to use the SKEW function as a worksheet function in Microsoft Excel:
Example of SKEW Function in Excel (Positively Skewed in Excel):
Column A has a distribution of values. Skewness these values can be calculated using formula
Syntax: =SKEW(A2:A21)
Result: 0.495553072
as shown in the above example. This result in the value of 0.495553072. which indicates positive skew.
Example of SKEW Function in Excel (Negatively Skewed in Excel):
Column A has a distribution of values. Skewness these values can be calculated using formula
Syntax: =SKEW(A2:A21)
Result: 0.495553072
as shown in the above example. This result in the value of 0.773509377which indicates negative skew
Note:
 Arguments can either be numbers or names, arrays, or references that contain numbers.
 Logical values and text representations of numbers that you type directly into the list of arguments are counted.
 If an array or reference argument contains text, logical values, or empty cells, those values are ignored; however, cells with the value zero are included.
 Arguments that are error values or text that cannot be translated into numbers cause errors.
 If there are fewer than three data points, or the sample standard deviation is zero, SKEW returns the #DIV/0! error value.

The equation for skewness is defined as: