Count conditional observations in a DATA step or how to use COUNT () in a DATA step to count

[d6k5d3]

I have the following:

data have;
  input Sl  Return;
datalines;
 1  4.5563
 2  4.8562
 3  0.0000
 4  3.5879
 5  0.0000
 6  0.0000
 7  0.0000
 8  0.0000
 9  2.5879
10  3.6879
run;

I know I can use PROC SQL to count observations, but I would need to do the same in a DATA step. I want:

DATA want;

set HAVE;

count number of observations if return= 0;

zero_ret_perc= (number of observations with zero returns/ total number of observations)*100;

run;

How can I achieve this?

Much thanks.

[novinosrin · Accepted solution]

data have;
  input Sl  Return;
datalines;
 1  4.5563
 2  4.8562
 3  0.0000
 4  3.5879
 5  0.0000
 6  0.0000
 7  0.0000
 8  0.0000
 9  2.5879
10  3.6879
run;


data want;
set have nobs=nobs end=lr;
zero_ret+ return=0;
if lr;
zero_ret_perc= (zero_ret/nobs)*100;
run;