Copying data in one cell to an empty cell while

[deleted_user]

I have a SAS dataset that contains multiple records for many persons. Persons are identified by SSN. The data must be de-identified so I created a var named PerID and populated it with a random digit number using FIRST.SSN. Now I want to copy the value of PerID for each of the first SSNs to the remainder each SSN. Note that the number of records for each person may range from 1 to 20.

[Cynthia_sas]

Hi:
It sounds like you've already discovered BY group processing and FIRST.byvar. If you check into the workings of the RETAIN statement, you will find your answer.
http://support.sas.com/documentation/cdl/en/lrdict/63026/HTML/default/viewer.htm#/documentation/cdl/...

cynthia