data a;
input x $  y @ ;
cards;
a 10
a 20
a 25
b 30
b 50
;
data b;
set a;
z=0;
if 0<y<=20 then z=1;
if 21<y<=40 then z=2;
if 41<y<=50 then z=3;
run;
proc sql;
  select z label='区间', sum(y) as total label='流量总和' ,count(*) as n label='个数'
   from b
   group by z;
quit;

谢谢...............!

想问一下这个问题可以用FORMAT实现吗?

proc format;
  value level
  0-20   = level1
  20<-40 = level2
  40<-50 = level3;
run;

data a;
input x $ y;
cards;
a 10
a 20
a 25
b 30
b 50
;

proc report data=a nowd;
  column y=ylevel y=ycount y=ysum;
  define ylevel/group format=level.;
  define ycount/analysis n;
  define ysum/analysis sum ;
run;