How are you adding the dates to the table?
What does your table structure look like?

You could take the Week of Year number and just integer divide it by 2.

I have one table that contains a date field and a pay period field. In the date field, I list each day of the year in mm/dd/yyyy format (1/1/2024, 1/2/2024, etc through year). In the pay period field, I list the number (1-26) corresponding to the payroll date, for example 1/1/2024 - 1/14/2024 might be '1', 1/15/2024 - 1/21/2024 might be 2 and so on (depending on pay date), until I have grouped all dates into their appropriate payroll period. The idea is to join this table to a transaction table, by date field, so that I can match the date to the corresponding pay period.  I am building a cash flow system.

How do you determine the pay period? Is it based on the first day of the year? First full week of the year? There are a lot of different methods for determining "the first week of the year" from an accounting standpoint.

I am starting with 1/3/24, because its my first pay period of 2024.  I am building this for my own use.

Right, but if you want to codify it in your database for future years, we need a rule to use for your algorithm.