/* the file name  meanbig.sas  */
data  mean3_1 ;
    input  siliao  $  weekage  addweigh  @@ ;
    cards ;
a  1  6.65  a  2  6.35  a  3  7.05  a  4  7.90  a  5  8.04  a  6  4.45
b  1  5.34  b  2  7.00  b  3  7.89  b  4  7.05  b  5  6.74  b  6  7.28
;
proc  sort  out=bigsort;
  by  siliao ;
run ;
proc  means ;
  by  siliao ;
run ;