Relative frequency compares the frequency of a particular value to the entire sample.
A relative frequency table compares the number of entries in each of several categories to the number of entries in the entire population. To begin building a relative frequency table, start by grouping values into categories, classes, or intervals, depending on the type of data. Once you have all of your data separated into separate classes or categories, tally the number of values in each category and the total number of values all together. To calculate the relative frequency of each category, divide the category, class, or interval frequency by the overall frequency.
Note: All the relative frequencies should add up to 1.0
Cumulative frequency is a running total of all non-relative frequencies up to and including the current category. To calculate a cumulative frequency, simply create a frequency distribution table, then add the frequency from the first category to that of the second category, then add that total frequency to the third category, and so on, up to and including the current category.
A relative cumulative frequency table shows how the cumulative frequency after each successive interval compares to the total frequency. To create a relative cumulative frequency table, calculate the relative frequency of each interval or category, and then add the relative frequency of each category to all the prior ones.