This is something easy, I guess. Whats the best way in which I can expand this
where clause to encompass a to field.
%LET from_mm = 02;
%Let from_yy = 2001;
*%Let to_mm = 03;
data lookup(keep=dset drop=lot);
where (month(lotdate)=&from_mm and year(lotdate)=&from_yy);