It does not:
1 data _null_; 2 do date = '1jan2024'd to '7jan2024'd; 3 week_u=week(date, 'u'); 4 week_v=week(date, 'v'); 5 week_w=week(date, 'w'); 6 format date yymmdd10.; 7 put (_ALL_) (=); 8 end; 9 run; date=2024-01-01 week_u=0 week_v=1 week_w=1 date=2024-01-02 week_u=0 week_v=1 week_w=1 date=2024-01-03 week_u=0 week_v=1 week_w=1 date=2024-01-04 week_u=0 week_v=1 week_w=1 date=2024-01-05 week_u=0 week_v=1 week_w=1 date=2024-01-06 week_u=0 week_v=1 week_w=1 date=2024-01-07 week_u=1 week_v=1 week_w=1 NOTE: DATA statement used (Total process time): real time 0.01 seconds cpu time 0.01 seconds
Did you read documentation for week()?
The documentation explains it clearly
The WEEK function with the U descriptor reads a SAS date value and returns the number of the week within the year. The number-of-the-week value is represented as a decimal number in the range 0–53, with a leading zero and maximum value of 53. Week 0 means that the first day of the week occurs in the preceding year. The fifth week of the year is represented as 05.
And search within the SAS documentation.
Depending on your install the online help could be quite extensive and no reason to "google".
Registration is open! SAS is returning to Vegas for an AI and analytics experience like no other! Whether you're an executive, manager, end user or SAS partner, SAS Innovate is designed for everyone on your team. Register for just $495 by 12/31/2023.
If you are interested in speaking, there is still time to submit a session idea. More details are posted on the website.
Learn how use the CAT functions in SAS to join values from multiple variables into a single value.
Find more tutorials on the SAS Users YouTube channel.