In this article, we will show how to calculate pooled variance in Excel with easy steps using vivid illustrations.

**Table of Contents**hide

**What Is Pooled Variance?**

Pooled Variance is a statistical term also known as combined variance or composite variance. It indicates the average variance of two or groups. It is the single common variance among the groups. Mathematically **Pooled Variance** can be shown as:

Where,

**n _{1Â }**= Sample size of

**Group 1**,

**n _{2 }**= Sample size of

**Group 2**,

**S _{1}**

**= Variance of**

^{2 }**Group 1**,

**S _{2}^{2 }**= Variance of

**Group 2**,

**S _{p}^{2}** = Pooled Variance

When the sample sizes are the same (**n _{1}=n_{2}**), then we can use this simplified formula.

**How to Calculate Pooled Variance in Excel: with Easy Steps**

**Step 1: Input Data and Form a Table**

In this step, we will collect sample data to make a dataset and form a **Table**. This **Table **will make our calculation easy.

- Insert sample data from two different sources into two columns
**Group 1**and**Group 2**in**Excel**. - Now, we will form two tables. Select the cells of
**the Group 1Â**column. - Then choose
**Table**from the**InsertÂ**tab.

- Now,
**Create Table**window appears. - Our selected range is shown here. Check
**My table has headersÂ**option. - Finally, press
**OK**.

- Now, click on the
**Table DesignÂ**tab. - Uncheck
**Filter Button**and**Banded Rows**from**Table Style Options**. - After that, set the name of the table in the
**Table NameÂ**section.

- Similarly, create the other table named
**Group2**. Have a look at the dataset. The little arrow in the bottom-right corner of the table denotes that, itâ€™s a â€˜tableâ€™. You can modify a table in size with this.

**Read More: **How to Do Variance Analysis in Excel

**Step 2: Count the Number of Samples**

**The COUNT function** counts the number of cells in a range that contains numbers.

In this step, we will determine the size of the sample data using the **COUNT **function.

- First, add a row to determine the sample size.

- Go to
**Cell C16**of the**Group 1Â**column. Put the following formula on that cell.

`=COUNT(Group1)`

- Then, press the
**EnterÂ**button.

We get the data size of **Group1**.

- Put the similar formula referring to the
**Group2**table.

**Read More: **How to Apply Variance Formula in Excel to Get Plus-Minus Results

**Step 3: Calculate Variance with Excel VAR.S Function**

The** VAR.S **function estimates variance based on a sample (ignores logical values and text in the sample).

In this step, we will determine the variance. Excel has a default function for this.

- We add a new row to calculate variance in the dataset.

- Go to
**Cell****C17**and put the following formula.

`=VAR.S(Group1)`

- Press the
**Enter**button to get the result.

We get the variance for the data of the **Group 1** column.

- Create a similar formula for
**Group 2**and put that on**Cell D17**and press**Enter**to get the result.

As we are using **Table **as the reference **Fill Handle** feature does not work here.

**Read More: **How to Calculate Sample Variance in Excel

**Step 4: Determine Pooled Variance with Formula**

Finally, we will calculate the **Pooled Variance**. We will apply a mathematical formula.

- Add a row for the
**Pooled Variance**.

- Put the formula on
**Cell C18**.

`=((C16-1)*C17+(D16-1)*D17)/(C16+D16-2)`

- Press the
**Enter**button to get the result.

As we previously mentioned, when the sample size is the same as that time, we can use a simplified formula.

- Now, apply that simplified formula to
**Cell C19**.

`=(C17+D17)/2`

- Again, press the
**Enter**button to get the result.

**Read More:** How to Calculate Percentage Variance between Two Numbers in Excel

**Download Practice Workbook**

Download this practice workbook to exercise while you are reading this article.

**Conclusion**

In this article, we described each step to calculate the pooled variance in Excel. I hope this will satisfy your needs.