Cumulative frequency is a statistical concept that represents the total number of observations that fall below or above a particular value in a dataset. It is calculated by successively adding the frequencies of each class interval up to a specified point. This running total allows researchers to understand how many data points lie within certain ranges, making it easier to analyze distributions.

Calculation Steps

1. Create a Frequency Distribution Table: Begin with a frequency distribution table that lists the class intervals and their corresponding frequencies.
2. Initialize Cumulative Frequency: The cumulative frequency for the first class interval is simply its frequency.
3. Add Frequencies: For each subsequent class interval, add its frequency to the cumulative frequency of the previous interval. This can be expressed mathematically as: Cumulative Frequency=Frequency of Current Class+  
4. Continue Until Complete: Repeat this process for all class intervals until you have calculated cumulative frequencies for the entire dataset.