May I ask what you will do with this additional column that contains the average? Are you trying to find out how far above or below the average the value of variable VALUE is? Or do you have some other reason for doing this, if so, what? (Really, explain the reason why you want this; explaining the reason should always be a part of your original post, we shouldn't have to ask)
If you are trying to find out how far above or below the average the value of variable VALUE is, then use PROC STDIZE, no extra column needed.
proc stdize data=have method=mean out=want;
var value;
by year;
run;
Also, we have in the past asked you to not provide data as screen captures, but as working SAS data step code. Please do that in the future.
--
Paige Miller