SKEW

Statistical Functions

(4.7/5)

Returns the skewness of a distribution. Skewness measures the asymmetry of a distribution around its mean. Positive skewness indicates right tail is longer; negative skewness indicates left tail is longer. Zero indicates symmetric distribution. Essential for understanding distribution shape, detecting asymmetry, and statistical analysis.

Interactive Formula Tester

Numbers:

Formula:

=SKEW("10, 20, 30, 40, 50")

Complete Theory & Understanding

Master the fundamentals of Excel SKEW function

Core Concept

The SKEW function returns the skewness of a distribution. Skewness measures the asymmetry of a distribution around its mean. Positive skewness (SKEW > 0) indicates the right tail is longer - outliers/extreme values are on the right, mean is typically greater than median. Negative skewness (SKEW < 0) indicates the left tail is longer - outliers/extreme values are on the left, mean is typically less than median. Zero skewness (SKEW = 0) indicates a symmetric distribution. Requires at least 3 values. Essential for understanding distribution shape, detecting asymmetry, statistical analysis, and determining if data transformation is needed.

Why Use SKEW?

Analyze distribution shape
Skewness in statistics
Determine if transformation needed
Detect process asymmetry

Key Characteristics

Measures Asymmetry

Distribution asymmetry around mean

Positive = right tail, Negative = left tail

Range -∞ to +∞

Can be any real number

Positive, negative, or zero

Minimum 3 Values

Requires at least 3 numbers

SKEW needs distribution to measure

Distribution Shape

Describes tail behavior

0 = symmetric, |SKEW| > 1 = highly skewed

Function Anatomy

=SKEW(parameters...)

Required

Parameters:

Function-specific parameters

Returns

Return Value:

Function-specific return type

Primary Use Cases

Distribution Analysis

Analyze distribution shape

Statistical Analysis

Skewness in statistics

Data Transformation

Determine if transformation needed

Quality Control

Detect process asymmetry

Theory Summary

Precise

Exact matching required

Position-Based

Returns numeric position

Error-Safe

Handles missing text gracefully

Syntax & Parameters

=SKEW(number1, number2)

Required

number1:

First number, cell reference, or range.

Optional

number2:

Additional numbers, cell references, or ranges (up to 255 arguments).

Returns

Return Value:

The skewness of the distribution

Description: Returns the skewness of a distribution

Interactive Examples

Basic SKEW

Calculate skewness

Input Text:

"10, 20, 30, 40, 50"

Formula:

=SKEW(10, 20, 30, 40, 50)

Result:

Returns approximately 0 for symmetric data. SKEW measures asymmetry: positive = right tail, negative = left tail, 0 = symmetric.

VBA Implementation & Automation

Basic SKEW in VBA

Use SKEW function in VBA

' Basic SKEW in VBA
Range("C1").Value = Application.WorksheetFunction.Skew(Range("A1:A10"))
' Returns: Skewness value

' Calculate skewness
Sub CalculateSkewness()
    Dim skewValue As Double
    skewValue = Application.WorksheetFunction.Skew(Range("A1:A10"))
    Range("B1").Value = skewValue
End Sub

' Interpret skewness
Sub InterpretSkewness()
    Dim skewValue As Double
    Dim interpretation As String
    skewValue = Application.WorksheetFunction.Skew(Range("A1:A10"))
    
    If Abs(skewValue) > 1 Then
        interpretation = "Highly skewed"
    ElseIf Abs(skewValue) > 0.5 Then
        interpretation = "Moderately skewed"
    Else
        interpretation = "Approximately symmetric"
    End If
    
    Range("B1").Value = "SKEW: " & skewValue
    Range("B2").Value = interpretation
End Sub

' Compare with mean and median
Sub CompareSkewMeanMedian()
    Dim skewValue As Double
    Dim meanValue As Double
    Dim medianValue As Double
    skewValue = Application.WorksheetFunction.Skew(Range("A1:A10"))
    meanValue = Application.WorksheetFunction.Average(Range("A1:A10"))
    medianValue = Application.WorksheetFunction.Median(Range("A1:A10"))
    Range("B1").Value = "SKEW: " & skewValue
    Range("B2").Value = "Mean: " & meanValue
    Range("B3").Value = "Median: " & medianValue
    ' Positive skew: mean > median typically
    ' Negative skew: mean < median typically
End Sub

' Distribution analysis
Sub DistributionAnalysis()
    Dim skewValue As Double
    Dim kurtValue As Double
    skewValue = Application.WorksheetFunction.Skew(Range("A1:A10"))
    kurtValue = Application.WorksheetFunction.Kurt(Range("A1:A10"))
    Range("B1").Value = "Skewness: " & skewValue
    Range("B2").Value = "Kurtosis: " & kurtValue
    Range("B3").Value = "Shape: " & IIf(Abs(skewValue) > 1, "Highly skewed", "Moderately symmetric")
End Sub

Business Applications

Distribution Analysis

Analyze distribution shape

=SKEW(data_distribution)

Statistical Analysis

Skewness in statistical analysis

=SKEW(sample_data)

Data Transformation

Determine if transformation needed

=SKEW(values)

Quality Control

Detect process asymmetry

=SKEW(process_data)

Common Issues & Solutions

#DIV/0! Error

SKEW returns #DIV/0! with less than 3 values

=IF(COUNT(A1:A10)>=3, SKEW(A1:A10), "Need 3+ values")

Solution: SKEW requires at least 3 numeric values. With 0, 1, or 2 values, it cannot calculate skewness. Ensure you have at least 3 numeric values in the range.

Understanding Values

Difficulty interpreting SKEW

|SKEW| > 1 = highly skewed

SKEW vs KURT

Uncertainty about difference

SKEW = asymmetry, KURT = tail weight

Solution: SKEW measures asymmetry (tail direction). KURT measures tail weight and peak height. Both describe distribution shape but measure different aspects.