Change valut in dataset to missing

[MCB1]

Hi,

I have a dataset with 7 individuals (ID) and 2 households (FAM). In addition, I have two variables, Ink and Disp. Ink shows the individual's income while Disp shows the households' disposable income. Disp thus repeats itself. I want the variable disp to be kept for the first individual in the household and get a value missing for the rest of the individuals in the household. Below is the code that shows what I have and how I want it to be. thank you!

DATA HAVE;
INPUT ID FAM INK DISP;

DATALINES;

1 1 50 60

2 1 100 60

3 1 200 60

4 2 500 250

5 2 700 250

6 2 0 250

7 2 0 250

;

RUN;

DATA WANT;

INPUT ID FAM INK DISP;

DATALINES;

1 1 50 60

2 1 100 .

3 1 200 .

4 2 500 250

5 2 700 .

6 2 0 .

7 2 0 .

;

RUN;

[PeterClemmensen · Accepted solution]

data want;
   set have;
   by fam;
   if not first.fam then disp = .;
run;