preloadfmt and proc summary

[SASPhile]

proc format;
value $YN
'Y'='Yes'
'N'='No'
Other='Missing';
run;
dataset has 20 records and one of the variable is smoking.All records for smoing are Blanks.

I applied the format to smoking variable in Proc summary using preloadfmt.

I want to display Missing as 20 . When I run proc summary I see the below counts:

proc summary data = ads1 n completetypes;
by popfl ;
class smoking / preloadfmt ;
var dummy;
output out = want n=count;
format smoking $YN.;
run ;

Missing 0
Yes 0
No 0

Where am I going wrong?

[data_null__ · Accepted solution]

You need the missing option.

When counting with PROC SUMMARY you can use _FREQ_ no need for dummy.

proc format;
   value $YN
      'Y'='Yes'
      'N'='No'
      Other='Missing';
   run;
data adsl;
   do id = 1 to 20;
      smoking = ' ';
      output;
      end;
   run;
proc summary data=adsl nway completetypes missing;
   *by popfl;
   class smoking / preloadfmt;
   output out = want;
   format smoking $YN.;
   run;
proc print;
   run;

[data_null__]

You might want to only show the missing row when there are missing values.  Here is one way to accomplish that by recoding blank SMOKING to "Missing"

data adsl;
   length smoking $8;
   do id = 1 to 20;
      smoking = chooseC(rantbl(4,.5,.5,.1),'Y','N','Missing');
      output;
      end;
   run;
proc print;
   run;
proc format;
   value $YN(notsorted default=8) 
      'Y'='Yes'
      'N'='No'
      ;
   quit;
proc summary data=adsl nway completetypes missing;
   class smoking / preloadfmt order=data;
   output out=want / levels;
   format smoking $YN.;
   run;
proc print;
   run;