sas is the column an even year? - sql

Question

I currently have data regarding income streams over four years, the income stream fills a 4x4 matrix as follows:
Year1 Year2 Year3 Year4
2017 10 15 20 25
2018 10 15 20 25
2019 10 15 20 25
2020 10 15 20 25
The income streams come from a debt instrument where the rows indicate when the debt was issued and the columns indicate the flow of income coming in per year.
I am trying to build another matrix to highlight whether or not the debt instrument was priced that year to create this matrix:
Year1 Year2 Year3 Year4
2017 1 0 0 0
2018 0 1 0 0
2019 0 0 1 0
2020 0 0 0 1
This is a very simple example and it goes on to work on how often the instrument is repriced etc. for simplicity, is there a way to create an if or where function that returns a 1 or 0 depending on whether the year is equal to or within a certain amount of time of the instrument being issued.
So far i'm thinking along the lines
%Repricing = 1
data want;
set have;
if Year[i] <= &Repricing;
then Year[i]=1;
run;
It's probably obvious that SAS isn't my language of choice, TIA.

Answer 1

Here's one way to do this, but I basically renamed the years to match the years of data - this is logic that was in your text but not in your data.
*sample data;
data have;
input YearD Year2017 Year2018 Year2019 Year2020;
cards;
2017 10 15 20 25
2018 10 15 20 25
2019 10 15 20 25
2020 10 15 20 25
;
run;
data want;
set have;
*arrays for years and flags;
array _year(2017:2020) year2017-year2020;
array _flag(2017:2020) flag2017-flag2020;
*loop over array;
do i=2017 to hbound(_year);
/*check if year matches year in variable name*/
if put(yearD, 4.) = compress(vname(_year(i)),, 'kd')
then _flag(i)=1;
else _flag(i)=0;
end;
drop i;
run;