I like Barry's 1st answer   and below is how you would do for his second suggestion. get the list of variables that needs to be passed to the macro and send them all to a macro variable separating them by a special character, say LIST for example: the macro variable LIST would be like this A*B*C*D*............*Z now loop it through all the parameters %do i=1 %to 50;      %let param=%scan(&list,&i,'*');      %CT(param1=data, param2=inv, param3=&param); %end; hope this helps. ... View more

data have; input Firm $     Year     INDEX ; cards; A          2001     0              A          2002     1              A          2003     1              A          2004     1              A          2005     1              A          2006     1              A          2007     1              A          2008     1              A          2009     0              B          2001     0              B          2002     0              B          2003     1              B          2004     1              B          2005     1              B          2006     1              B          2007     0           ; proc sort data=have out=index0; by firm year; where index=0; run; proc sort data=have out=index1; by firm year; where index=1; run; data index1; set index1; retain seq; by firm year; if first.firm then seq=1; else seq+1; if seq>1 then ongoing=1; else ongoing=0; if 2<=seq<=3 then ongoing1=1; else ongoing1=0; if seq>3 then ongoing2=1; else ongoing2=0; run; data final; set index0(in=a) index1; if a then do; ongoing=0; ongoing1=0; ongoing2=0; end; run; hope this helps... Regards ... View more