Thanks so much for your reply, Ballardw.
I was indeed running "Server" SAS EG - and this turned out to be SAS EG Version 5.1. However, the datasets were created using Proc Survey Select in Base SAS (non-Server) Version 9.4. I have been told that, in our department, only EG Version 7.1 is compatible with SAS 9.4, and it turned out that when I ran the code on SAS EG 7.1, I got the same results as before.
(Btw, the IT people also found an OS issue, since my system was upgraded to Windows 10 - can't say I fully understood the issue, so not commenting.)
Seems like there is a lot that goes on in the background behind these versions of SAS!
Thanks again!
... View more