大概这样就可以了
proc transpose data a
out=b;
by count;
id _id;
var var1-var3;
run;

data test;
   input id (var1 var2 var3) ($) count;
cards;
1 A1 A2 A3 1
1 B1 B2 B3 2
1 C1 C2 C3 3
2 D1 D2 D3 1
2 F1 F2 F3 2
;
run;

proc sort data=test;
   by count;
run;

proc transpose data=test out=want prefix=var;
   var var1 var2 var3;
   by count;
run;