The variable in the FREQ statement identifies the variable (in the input data set) containing the frequency of occurrence of each observation. PROC PHREG treats each observation as if it appears n times, where n is the value of the FREQ variable for the observation. If not an integer, the frequency value is truncated to an integer. If the frequency value is missing, the observation is not used in the estimation of the regression parameters.

The following option can be specified in the FREQ statement after a slash (/):