Date:         Thu, 24 Sep 2009 13:51:55 -0400
Reply-To:     Norm Weston <nweston@AMGEN.COM>
Sender:       "SAS(r) Discussion" <SAS-L@LISTSERV.UGA.EDU>
From:         Norm Weston <nweston@AMGEN.COM>
Subject:      Re: last date of contact

I am sure that there will be several ways of doing this.  Personally, I
would transpose the dataset and then sort in order by your date field(s).
Then you could rename or create a new field based on that.  Something like
this;

proc sort data=have;
by header-vars;
run;

proc transpose data=have out=trans;
by header-vars;
var date vars;
run;

proc sort data=trans;
by header-vars and new-date-val;
run;

data last_contact;
 set trans;
 by header-vars;
 if last.header-vars then output;
run;

From there you can stack them back, or do whatever you were planning on
doing with the data (i.e. retranspose back and attach, or whatever).