

FREQ   variable   ; 
            
The FREQ statement lists a numeric variable whose value represents the frequency of the observation. If you use the FREQ statement,
            the procedure assumes that each observation represents 
 observations, where 
 is the value of the FREQ variable. If 
 is not an integer, SAS truncates it. If 
 is less than 1 or is missing, the observation is excluded from the analysis. The sum of the frequency variable represents
            the total number of observations. 
         
The effects of the FREQ and WEIGHT statements are similar except when calculating degrees of freedom.