how to calculate age

[hjjijkkl]

I have a data with variables for day month and year and i want to calculate the age of the subject.

id	month	day	year
1	1	27	1985
2	10	12	2002
3	5	20	1990

the output will look like this 

id	Calculated age
1	36
2	18
3	30

[PeterClemmensen]

Try this

data have;
input id month day year;
datalines;
1 1  27 1985
2 10 12 2002
3 5  20 1990
;

data want(drop = dob);
   set have;
   dob = mdy(month, day, year);
   age = int(yrdif(dob, today(), 'act/act'));
run;

Result:

id  month  day  year  age 
1   1      27   1985  36 
2   10     12   2002  18 
3   5      20   1990  30 

[ballardw]

Age requires TWO date values. Which specific date is the shown month, day and year to be compared with?

It is also always a good idea to indicate what units something like age is reported in. I deal with data where age in different sets is days, weeks, months, occasionally weeks and months,   and years depending on the subject of the report.