Cumulative Frequency Polygon

A frequency polygon whose vertices represent the sum of all previous class frequencies of the data. For example, if a frequency polygon had vertices of 5, 8, 3, 7, and 10, the cumulative frequency polygon on the same data would have vertices of 5, 13, 16, 23, and 33. As another example, a cumulative frequency distribution for scores on a psychology test is shown below.