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Excel CORREL Function

last modified April 4, 2025

The CORREL function calculates the correlation coefficient between two data sets. It measures how closely two variables move in relation to each other. This tutorial provides a comprehensive guide to using the CORREL function with detailed examples. You'll learn basic syntax, practical applications, and interpretation of results.

CORREL Function Basics

The CORREL function returns the Pearson correlation coefficient. It ranges from -1 to 1, indicating negative to positive correlation. A value of 0 means no correlation exists between the variables.

Component Description
Function Name CORREL
Syntax =CORREL(array1, array2)
Arguments Two required ranges of equal size
Return Value Correlation coefficient (-1 to 1)

This table breaks down the essential components of the CORREL function. It shows the function name, basic syntax format, argument requirements, and return value characteristics.

Basic CORREL Example

This example demonstrates the simplest use of CORREL with two small data sets. We'll examine the relationship between study hours and test scores.

A B C
Study Hours Test Scores
2 65
4 80
6 95
=CORREL(A2:A4,B2:B4)
Basic CORREL formula
=CORREL(A2:A4,B2:B4)

This formula calculates the correlation between study hours (A2:A4) and test scores (B2:B4). The result will be 1, indicating a perfect positive correlation. As study hours increase, test scores increase proportionally.

CORREL with Real-World Data

This example uses CORREL with larger data sets to analyze the relationship between temperature and ice cream sales over 12 months.

A B C
Month Temperature (°F) Ice Cream Sales
Jan 32 150
Feb 35 180
Mar 45 220
... ... ...
Dec 28 120
=CORREL(B2:B13,C2:C13)
CORREL with monthly data
=CORREL(B2:B13,C2:C13)

This formula calculates the correlation between temperature (B2:B13) and ice cream sales (C2:C13). The result might be around 0.9, showing a strong positive correlation. Higher temperatures generally lead to increased ice cream sales.

CORREL with Negative Correlation

This example demonstrates negative correlation by examining the relationship between outdoor temperature and heating costs.

A B C
Month Temperature (°F) Heating Cost ($)
Jan 25 180
Feb 30 150
Mar 40 120
... ... ...
Dec 28 160
=CORREL(B2:B13,C2:C13)
CORREL showing negative relationship
=CORREL(B2:B13,C2:C13)

This formula calculates the correlation between temperature (B2:B13) and heating costs (C2:C13). The result might be around -0.85, indicating a strong negative correlation. As temperatures rise, heating costs typically decrease.

CORREL with No Correlation

This example shows data sets with no apparent relationship, demonstrating how CORREL identifies lack of correlation.

A B C
Day Number of Cats Seen Stock Market Index
1 3 10500
2 5 10480
3 2 10520
4 4 10510
5 3 10490
=CORREL(B2:B6,C2:C6)
CORREL with unrelated data
=CORREL(B2:B6,C2:C6)

This formula calculates correlation between cats seen (B2:B6) and stock market index (C2:C6). The result will be close to 0, indicating no meaningful relationship. CORREL helps identify when variables are statistically independent.

CORREL with Different Sized Ranges

This example demonstrates what happens when the input ranges have different sizes, which causes an error in Excel.

A B C
X Values Y Values
10 20
15 25
20
=CORREL(A2:A4,B2:B3)
CORREL with mismatched ranges
=CORREL(A2:A4,B2:B3)

This formula attempts to correlate range A2:A4 (3 values) with B2:B3 (2 values). Excel returns a #N/A error because the ranges must be the same size. Always verify range sizes when using CORREL.

CORREL with Text and Empty Cells

This example shows how CORREL handles ranges containing text values or empty cells.

A B C
X Values Y Values
5 10
Text 15
20
10 25
=CORREL(A2:A5,B2:B5)
CORREL with mixed data types
=CORREL(A2:A5,B2:B5)

This formula correlates ranges containing a text value (A3) and an empty cell (A4). CORREL ignores these non-numeric entries and calculates based on valid number pairs. The result uses only (5,10) and (10,25) from the complete ranges.

Interpreting CORREL Results

Understanding the correlation coefficient value is crucial for proper analysis. Here's a guide to interpreting CORREL results.

Correlation Value Interpretation
1.0 Perfect positive correlation
0.7 to 0.9 Strong positive correlation
0.4 to 0.6 Moderate correlation
0.1 to 0.3 Weak correlation
0 No correlation
-0.1 to -0.3 Weak negative correlation
-0.4 to -0.6 Moderate negative correlation
-0.7 to -0.9 Strong negative correlation
-1.0 Perfect negative correlation

This table provides guidelines for interpreting CORREL results. Remember that correlation doesn't imply causation. Always consider context when analyzing relationships between variables.

The CORREL function is a powerful tool for statistical analysis in Excel. It helps identify relationships between variables, whether positive, negative, or nonexistent. Proper interpretation of results is essential for making data-driven decisions. CORREL works best with clean, numeric data sets of equal size.

Author

My name is Jan Bodnar, and I am a passionate programmer with extensive programming experience. I have been writing programming articles since 2007. To date, I have authored over 1,400 articles and 8 e-books. I possess more than ten years of experience in teaching programming.

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