Note down the 1st value in Frequency Distribution Table of possible occurrence of data. For instance, in one year 200 deer weighing 50 kg or less are caught is first cumulative frequency for distribution.
Next we sum up the succeeding value in the data Set and initial cumulative frequency value. In our example we have 200 deer weighing 50 kg or less were caught in the 1 year. Considering next value in the set to be 250 deer weighing 60 kg, we add 250 to 200 to the sum total of 450 deer. Now as current range of values have been changed from 50 kg to 60 kg, cumulative frequency now is 250 deer weighing 60 kg or less.
In this way we keep on adding successive data values as number of deer caught year wise to resulting cumulative frequencies to get final cumulative frequency of the given distribution of data values. Corresponding cumulative table with initial cumulative frequency value of 200 deer weighing 50 kg or less can be made as follows: