If the pension fund is set up as a fixed amount in the employee management, it is not necessary to scroll through them all to make any changes at the beginning of the year.
Go to the employee management :
Click on the Selective Update tab:
Click on the pension fund item :
The Code column has zeros in it, meaning that these are fixed amounts (if they were rates, they would be 1).
Enter the amounts for the new year that would change.
When you have done this, do not forget to click on Apply :