Add a count column

[Jose7]

Hi experts 

I have a table like this

Id	Name	Percentage
1	Ricardo	100
2	Jose	100
3	Roberto	50
3	Alexander	50
4	Carlos	100
5	William	50
5	Juan	50
6	Alonso	33
6	Perez	33
6	Menjivar	34
7	Regina	100

And i Want to add a column making a count like this

Id	Name	Percentage	Count
1	Ricardo	100	1
2	Jose	100	1
3	Roberto	50	1
3	Alexander	50	2
4	Carlos	100	1
5	William	50	1
5	Juan	50	2
6	Alonso	33	1
6	Perez	33	2
6	Menjivar	34	3
7	Regina	100	1

Do you have any idea how to make it ?

[Kurt_Bremser · Accepted solution]

data want;
set have;
by id;
if first.id
then count = 1;
else count + 1;
run;

The SUM Statement in the ELSE implies an automatic RETAIN of the new variable.

[Jose7]

Thks! it works !