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A **frequency table **is a table that displays information about frequencies. Frequencies simply tell us how many times a certain event has occurred.

For example, the following table shows how many items a shop sold in different price ranges in a given week:

Item Price | Frequency |
---|---|

$1 – $10 | 20 |

$11 – $20 | 21 |

$21 – $30 | 13 |

$31 – $40 | 8 |

$41 – $50 | 4 |

The first column displays the price class and the second column displays the frequency of that class.

It’s also possible to calculate the **cumulative frequency **for each class, which is simply the sum of the frequencies up to a certain class.

Item Price | Frequency | Cumulative Frequency |
---|---|---|

$1 – $10 | 20 | 20 |

$11 – $20 | 21 | 41 |

$21 – $30 | 13 | 54 |

$31 – $40 | 8 | 62 |

$41 – $50 | 4 | 66 |

For example, the first cumulative frequency is simply equal to the first frequency of **20**.

The second cumulative frequency is the sum of the first two frequencies: 20 + 21 = **41**.

The third cumulative frequency is the sum of the first three frequencies: 20 + 21 + 13 = **54**.

And so on.

The following example illustrates how to find cumulative frequencies in Excel.

**Example: Cumulative Frequency in Excel**

First, we will enter the class and the frequency in columns A and B:

Next, we will calculate the cumulative frequency of each class in column C.

In the image below, Column D shows the formulas we used:

We can also create an ogive chart to visualize the cumulative frequencies.

To create the ogive chart, hold down CTRL and highlight columns A and C.

Then go to the **Charts **group in the **Insert **tab and click the first chart type in **Insert Column or Bar Chart**:

Along the top ribbon in Excel, go to the **Insert** tab, then the **Charts **group. Click **Scatter Chart**, then click **Scatter with Straight Lines and Markers**.

This will automatically produce the following ogive graph:

Feel free to modify the axes and the title to make the graph more aesthetically pleasing:

**Additional Resources**

Cumulative Frequency Calculator

How to Calculate Relative Frequency in Excel