Need to create a time varying measure within SAS

[jadenmcbroom]

I need to create a new variable based on care interruption. RICF represents how many years from the event of interest. So ricf1=1 year since event, ricf2=2 years since event, ricf3=3 years since event, etc;

I want to create a variable that states how many years till the first interruption (YTI) which are circled in red. So for example

obs    YTI

1        0

2        2

3        0

4        0

5        10

6        5

7        0 

8        3

9        9

10      1 

[novinosrin · Accepted solution]

data want;
 set have;
 array t ricf1-ricf10;
 _n_=whichn(0,of t(*))-1;
 yti=ifn(sign(_n_)=-1,dim(t),_n_);
run;