National Center for Health Statistics link:
Related to relative and relative cumulative frequencies:
In statistics, sometimes few numbers in the given data are repetitive a couple of times. This repetition of a particular number is called its frequency. The frequency of an item represents how many times that item appears in the data. On the other hand, relative frequency of a number is its frequency as compared to the total frequencies of all the numbers. Relative frequency is evaluated by dividing the individual frequency of an item by total number of frequencies. The formula for the relative frequency is given below
[img border=”0″ src=”https://ci5.googleusercontent.com/proxy/Ri8OAVLhr6r4i0TTVLp9cQlrchh0kTr6lMfqdj1zSsSMCgqtPXVso-Qkl7Fq1szZAUcLQwPzx_H2r9gH2RStwOHtnoOGNEpdUnbXVSjbUjJlOTpgvVKovnMVH-KHFU_i=s0-d-e1-ft#http://images.tutorvista.com/cms/images/113/relative-frequency-formula.png” alt=”Relative Frequency Formula” class=”CToWUd”>
f = Frequency of an individual item
n = Total frequencies.
Cumulative relative frequency is a statistical calculation figured by adding together previously tabulated relative frequencies that makes a running total along a frequency table. For instance, the first relative frequency of an occurrence is two out of 20 and the second relative frequency is five out of 20. The two frequencies are added together to make seven of 20, or 0.35 for a cumulative relative frequency.