data stock;
input id $ date $3-12 v1 v2;
cards;
A 2016-02-01 1.1 3.1
A 2016-02-02 3 3
A 2016-02-03 3 4
B 2016-03-01 3 4
B 2016-03-02 4 5
C 2016-04-01 1.1 3.1
C 2016-04-02 3 3
C 2016-04-03 3 4
C 2016-04-04 3 4
;
run;
proc sort data=stock; by id date; run;
data stock_sort;
set stock;
by id date;
if first.id then seq=0;
seq+1;
run;