Your problem is a list processing example: how to split a data set into groups this page has a macro that illustrates the parameter text=%nrstr(...) http://www.sascommunity.org/wiki/Macro_CallText Based on my reading of your Q and commentary this is the data step you want Data G_5      G_21         G_42      G_63         G_126         G_252; do until (EndoFile);    set Library.TheData        end = EndoFile;    if 0 <= cday <= 5   then output g_5;           if 0 <= cday <= 21  then output g_21 ;           if 0 <= cday <= 42  then output g_42 ;           if 0 <= cday <= 63  then output g_63 ;           if 0 <= cday <= 126 then output g_126;           if 0 <= cday <= 252 then output g_252;           end; stop; run; This is my solution. %Macro Do_(text=%nrstr(g_&Item)); %let list = 21                42             63             126             252; %local I;            %do I = 1 %to %sysfunc(countc(&List,%str()))+1;     %let item = %scan(&List,I);     %unquote(&Text)     %end; %mend;                DATA %do_(); do until (EndoFile);    set Library.TheData        end = EndoFile;    %do_(text=%nrstr(if 0 <= cday <= &item   then output g_&item;)           end; stop; run; This solution is from the HOW: http://www.sascommunity.org/wiki/List_Processing_Basics_Creating_and_Using_Lists_of_Macro_Variables Ron Fehd  loops maven ... View more