%macro crt_dynamic_fmt(din=, st=, lbl=, fmtname=);
     **** create dynamic format     ****;
     proc sort data=&din out=&fmtname nodupkey; by &st; run;
     data &fmtname;
        set &fmtname;
        retain fmtname type;
        fmtname="&fmtname";
        type='N';
        length start $200 label $200;
        start=strip(put(&st, best.));
        label=&lbl;
        keep fmtname type start label;
     run;
     proc format cntlin=&fmtname; run;

%mend crt_dynamic_fmt;

%crt_dynamic_fmt(din=fin, st=avisitn, lbl=avisit, fmtname=visn);