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Researchers often take samples from a population and use the data from the sample to draw conclusions about the population as a whole.

One commonly used sampling method isÂ **systematic sampling**, which is implemented with a simple two step process:

**1.** Place each member of a population in some order.

**2.** Choose a random starting point and select every n^{th} member to be in the sample.

The following step-by-step example shows how to perform systematic sampling in Excel.

**Step 1: Enter the Data**

First, letâ€™s enter the values for some dataset in Excel:

**Step 2: Enter Parameter Values**

Next, we need to decide how many values weâ€™d like to randomly sample. For this example, weâ€™ll choose a sample size of n = 4.

Next, weâ€™ll use the following formulas to calculate the population size, step size for our systematic sampling, and random starting point:

**Step 3: Label Each Data Value**

Our **RANDBETWEEN()** function randomly chose the value 3 as the starting point in our dataset. Thus, give the data value at position 3 a label of 1 and then number down to the step size of 5:

Next, type **=D4** in the next available cell:

Next, copy and paste this formula down to all remaining cells in column D. Then manually fill in the values at the top of the of column D:

**Step 4: Filter Values**

Lastly, we need to filter the dataset to only include data values that have a label of 1.

To do so, click the **Data** tab along the top ribbon. Then click the **Filter** icon. Then click the column called **Labels** and filter to only include rows that have a label with value 1:

Once you do so, the data will be filtered to only include data values that have a Label of 1:

This represents our sample of size 4.

**Additional Resources**

Introduction to Types of Sampling Methods

How to Select a Random Sample in Excel