Hello,   You can check for missing values using proc sql: proc sql noprint; select max(&varname) into :max_value from &dsname; quit; and afterwards just check the value of the newly created macro variable:   %if &max_value= or  &max_value=. %then %do; %put &varname has only missing values;%end;   ... View more

Hello, Here is a macro which also provides the desired result. %macro tocalc (nbvar); data want; set have; mc = span-(%eval(&nbvar) - N(of var1-var&nbvar)); %put var&nbvar; run; %mend tocalc; %tocalc(5); ... View more