Calculating day span across longitudinal data

[rupalif]

Hi,I am trying to calculate difference between two dates from two different rows. I have unique memberid, effective date and end date variables. for some members there are multiple rows. I want to calculate difference between End date and effective date from next row for that member.

thanks

[data_null__]

Something like this?

data long;
   input id s e;
   informat s e date9.;
   format s e date9.;
   cards;
1 10DEC2012 10FEB2013
1 17DEC2013 19FEB2014
2 10NOV2012 10FEB2013
2 10MAR2013 12APR2013
2 17DEC2013 19FEB2014
;;;;
   run;
data longnext;
   set long end=eof;
   by id;
   if not eof then set long(firstobs=2 keep=s rename=s=nxs);
   if not last.id then dif = nxs-e;
   run;
proc print;
   run;

[rupalif]

It worked! Thank you very much!!!