Date:         Mon, 20 Aug 2007 09:11:32 -0400
Reply-To:     Muthia Kachirayan <muthia.kachirayan@GMAIL.COM>
Sender:       "SAS(r) Discussion" <SAS-L@LISTSERV.UGA.EDU>
From:         Muthia Kachirayan <muthia.kachirayan@GMAIL.COM>
Subject:      Re: finding date difference
In-Reply-To:  <1187611319.721426.74330@x35g2000prf.googlegroups.com>
Content-Type: text/plain; charset=ISO-8859-1

Murugesh,

Try this. You can do it without using LAG function. Assumed that custnum =
107262 is valid.


data given;
input custnum invnum $ invdate mmddyy8.;
cards;
1004159 I000698 01/16/07
1004159 I000699 02/17/07
1004159 I000700 02/23/07
1004159 I000701 03/06/07
1004159 I000702 05/11/07
1014885 I000703 01/25/07
1014885 I000704 02/04/07
1014885 I000705 02/16/07
1014885 I000706 02/25/07
1014885 I000707 04/05/07
1020600 I000709 01/06/07
1020600 I000710 01/15/07
1020600 I000711 01/26/07
1020600 I000712 03/29/07
1020600 I000713 05/13/07
1031528 I000715 01/27/07
1040996 I000716 02/23/07
1040996 I000717 03/04/07
1040996 I000718 03/09/07
1040996 I000719 03/13/07
1040996 I000720 04/07/07
1040996 I000721 05/07/07
1047016 I000723 01/11/07
1047016 I000724 04/03/07
1047016 I000725 04/30/07
1047016 I000726 05/01/07
1061037 I000727 01/30/07
1061037 I000728 02/07/07
1061037 I000729 03/13/07
1061037 I000730 05/17/07
107262 I000051 04/29/07
;
run;

proc sort data = given;
by custnum;
run;
data wanted;
do until(last.custnum);
    set given;
    by custnum;
    diff = invdate - prev;
    output;
    prev = invdate;
end;
drop prev;
run;

Regards,

Muthia Kachirayan