By default, each observation is counted only once in the calculation of the chart statistics. To calculate weighted statistics in which an observation can be counted more than once, use the FREQ= option. This option identifies a variable whose values are used as a multiplier for the observation in the calculation of the statistic. If the value of the FREQ= variable is missing, 0, or negative, the observation is excluded from the calculation.

If you use the SUMVAR= option, then for each observation, the value of the SUMVAR= variable is multiplied by the value of the FREQ= variable in calculating the chart statistic.

For example, to use a variable called COUNT to produce weighted statistics, assign FREQ=COUNT. If you also assign the variable HEIGHT to the SUMVAR= option, then the following table shows how the values of COUNT and HEIGHT would affect the statistic calculation: