getting count by group

[novinosrin]

Also , since you are giving us the impression you are using combination of by groups making it a distinct pair, notsorted will yield the same results

So with NOTSORTED Option

data want;
if 0 then set have;
do total=1 by 1 until(last.emp_id);
set have;
by  agt_no 	emp_id notsorted;
end;
run;